.\" Man page generated from reStructuredText.
.
.TH "RECORDS.CONFIG" "5" "January 24, 2017" "7.0" "Apache Traffic Server"
.SH NAME
records.config \- the records.config file (by default, located in
/usr/local/etc/trafficserver/) is a list of configurable variables used by
the Traffic Server software. Many of the variables in records.config are set
automatically when you set configuration options with traffic_ctl config set. After you
modify records.config, run the command traffic_ctl config reload
to apply the changes. When you apply changes to one node in a cluster, Traffic Server
automatically applies the changes to all other nodes in the cluster
.
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.SH FORMAT
.sp
Each variable has the following format:
.INDENT 0.0
.INDENT 3.5
.sp
.nf
.ft C
SCOPE variable_name DATATYPE variable_value
.ft P
.fi
.UNINDENT
.UNINDENT
.SS Scope
.sp
All variables are defined within a scope, which is related to clustering, and
determines the level at which the variable is applied. The value for \fBSCOPE\fP
must be one of:
.TS
center;
|l|l|.
_
T{
Scope
T}	T{
Description
T}
_
T{
\fBCONFIG\fP
T}	T{
All members of the cluster.
T}
_
T{
\fBLOCAL\fP
T}	T{
Only the local machine.
T}
_
.TE
.SS Data Type
.sp
A variable\(aqs type is defined by the \fBDATATYPE\fP and must be one of:
.TS
center;
|l|l|.
_
T{
Type
T}	T{
Description
T}
_
T{
\fBFLOAT\fP
T}	T{
Floating point, expressed as a decimal number without units or
exponents.
T}
_
T{
\fBINT\fP
T}	T{
Integers, expressed with or without unit prefixes (as described
below).
T}
_
T{
\fBSTRING\fP
T}	T{
String of characters up to the first newline. No quoting necessary.
T}
_
.TE
.SS Values
.sp
The \fIvariable_value\fP must conform to the variable\(aqs type. For \fBSTRING\fP, this
is simply any character data until the first newline.
.sp
For integer (\fBINT\fP) variables, values are expressed as any normal integer,
e.g. \fB32768\fP\&. They can also be expressed using more human readable values
using standard unit prefixes, e.g. \fB32K\fP\&. The following prefixes are
supported for all \fBINT\fP type configurations:
.TS
center;
|l|l|l|.
_
T{
Prefix
T}	T{
Description
T}	T{
Equivalent in Bytes
T}
_
T{
\fBK\fP
T}	T{
Kilobytes
T}	T{
1,024 bytes
T}
_
T{
\fBM\fP
T}	T{
Megabytes
T}	T{
1,048,576 bytes (1024\s-2\u2\d\s0)
T}
_
T{
\fBG\fP
T}	T{
Gigabytes
T}	T{
1,073,741,824 bytes (1024\s-2\u3\d\s0)
T}
_
T{
\fBT\fP
T}	T{
Terabytes
T}	T{
1,099,511,627,776 bytes (1024\s-2\u4\d\s0)
T}
_
.TE
.sp
\fBIMPORTANT:\fP
.INDENT 0.0
.INDENT 3.5
Unless \fI\%proxy.config.disable_configuration_modification\fP is enabled,
Traffic Server writes configurations back to disk periodically. When doing so, the
unit prefixes are not preserved.
.UNINDENT
.UNINDENT
.sp
Floating point variables (\fBFLOAT\fP) must be expressed as a regular decimal
number. Unit prefixes are not supported, nor are alternate notations (scientific,
exponent, etc.).
.SS Additional Attributes
.SS Deprecated
.sp
A variable marked as \fIDeprecated\fP is still functional but should be avoided
as it may be removed in a future release without warning.
.SS Reloadable
.sp
A variable marked as \fIReloadable\fP can be updated via the command:
.INDENT 0.0
.INDENT 3.5
.sp
.nf
.ft C
traffic_ctl config reload
.ft P
.fi
.UNINDENT
.UNINDENT
.sp
This updates configuration parameters without restarting Traffic Server or interrupting
the processing of requests.
.SS Overridable
.sp
A variable marked as \fIOverridable\fP can be changed on a per\-remap basis using
plugins (like the \fIadmin\-plugins\-conf\-remap\fP), affecting operations within
the current transaction only.
.SH EXAMPLES
.sp
In the following example, the variable \fI\%proxy.config.proxy_name\fP is
a \fBSTRING\fP datatype with the value \fBmy_server\fP\&. This means that the
name of the Traffic Server proxy is \fBmy_server\fP\&.
.INDENT 0.0
.INDENT 3.5
.sp
.nf
.ft C
CONFIG proxy.config.proxy_name STRING my_server
.ft P
.fi
.UNINDENT
.UNINDENT
.sp
If the server name should be \fBthat_server\fP the line would be
.INDENT 0.0
.INDENT 3.5
.sp
.nf
.ft C
CONFIG proxy.config.proxy_name STRING that_server
.ft P
.fi
.UNINDENT
.UNINDENT
.sp
In the following example, the variable \fBproxy.config.arm.enabled\fP is
a yes/no flag. A value of \fB0\fP (zero) disables the option; a value of
\fB1\fP enables the option.
.INDENT 0.0
.INDENT 3.5
.sp
.nf
.ft C
CONFIG proxy.config.arm.enabled INT 0
.ft P
.fi
.UNINDENT
.UNINDENT
.sp
In the following example, the variable sets the cluster startup timeout
to 10 seconds.
.INDENT 0.0
.INDENT 3.5
.sp
.nf
.ft C
CONFIG proxy.config.cluster.startup_timeout INT 10
.ft P
.fi
.UNINDENT
.UNINDENT
.sp
The last examples configures a 64GB RAM cache, using a human readable
prefix.
.INDENT 0.0
.INDENT 3.5
.sp
.nf
.ft C
CONFIG proxy.config.cache.ram_cache.size INT 64G
.ft P
.fi
.UNINDENT
.UNINDENT
.SH ENVIRONMENT OVERRIDES
.sp
Every \fI\%records.config\fP configuration variable can be overridden
by a corresponding environment variable. This can be useful in
situations where you need a static \fI\%records.config\fP but still
want to tweak one or two settings. The override variable is formed
by converting the \fI\%records.config\fP variable name to upper
case, and replacing any dot separators with an underscore.
.sp
Overriding a variable from the environment is permanent and will
not be affected by future configuration changes made in
\fI\%records.config\fP or applied with \fBtraffic_ctl\fP\&.
.sp
For example, we could override the \fI\%proxy.config.product_company\fP variable
like this:
.INDENT 0.0
.INDENT 3.5
.sp
.nf
.ft C
$ PROXY_CONFIG_PRODUCT_COMPANY=example traffic_cop &
$ traffic_ctl config get proxy.config.product_company
.ft P
.fi
.UNINDENT
.UNINDENT
.SH CONFIGURATION VARIABLES
.sp
The following list describes the configuration variables available in
the \fI\%records.config\fP file.
.SS System Variables
.INDENT 0.0
.TP
.B proxy.config.product_company
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
Apache Software Foundation.UNINDENT
The name of the organization developing Traffic Server.
.INDENT 0.0
.TP
.B proxy.config.product_vendor
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
Apache.UNINDENT
The name of the vendor providing Traffic Server.
.INDENT 0.0
.TP
.B proxy.config.product_name
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
Traffic Server.UNINDENT
The name of the product.
.INDENT 0.0
.TP
.B proxy.config.proxy_name
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
build_machine.TP
.B Reloadable
Yes.UNINDENT
The name of the Traffic Server node.
.INDENT 0.0
.TP
.B proxy.config.bin_path
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
bin.UNINDENT
The location of the Traffic Server \fBbin\fP directory.
.INDENT 0.0
.TP
.B proxy.config.proxy_binary
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
traffic_server.UNINDENT
The name of the executable that runs the \fBtraffic_server\fP process.
.INDENT 0.0
.TP
.B proxy.config.proxy_binary_opts
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
\-M.UNINDENT
The command\-line options for starting Traffic Server.
.INDENT 0.0
.TP
.B proxy.config.manager_binary
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
traffic_manager.UNINDENT
The name of the executable that runs the \fBtraffic_manager\fP process.
.INDENT 0.0
.TP
.B proxy.config.env_prep
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
\fI*NONE*\fP.UNINDENT
The script executed before the \fBtraffic_manager\fP process spawns
the \fBtraffic_server\fP process.
.INDENT 0.0
.TP
.B proxy.config.config_dir
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
etc/trafficserver.UNINDENT
The directory that contains Traffic Server configuration files.
This is a read\-only configuration option that contains the
\fBSYSCONFDIR\fP value specified at build time relative to the
installation prefix. The \fB$TS_ROOT\fP environment variable can
be used alter the installation prefix at run time.
.INDENT 0.0
.TP
.B proxy.config.syslog_facility
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
LOG_DAEMON.UNINDENT
The facility used to record system log files. Refer to
\fIadmin\-monitoring\-logging\-understanding\fP for more in\-depth discussion
of the contents and interpretations of log files.
.INDENT 0.0
.TP
.B proxy.config.cop.core_signal
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
The signal sent to \fBtraffic_cop\fP\(aqs managed processes to stop them.
.sp
A value of \fB0\fP means no signal will be sent.
.INDENT 0.0
.TP
.B proxy.config.cop.linux_min_memfree_kb
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
The minimum amount of free memory space allowed before Traffic Server stops
the \fBtraffic_server\fP and \fBtraffic_manager\fP processes to
prevent the system from hanging.
.INDENT 0.0
.TP
.B proxy.config.cop.linux_min_swapfree_kb
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
The minimum amount of free swap space allowed before Traffic Server stops
the \fBtraffic_server\fP and \fBtraffic_manager\fP processes to
prevent the system from hanging. This configuration variable applies if
swap is enabled in Linux 2.2 only.
.INDENT 0.0
.TP
.B proxy.config.cop.init_sleep_time
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
The minimum amount of addtional duration allowed before Traffic Server detects
that the \fBtraffic_server\fP is not responsive and attempts a restart
during startup. This configuration variable allows Traffic Server a longer init
time to load potentially large configuration files such as remap config. Note that
this applies only during startup of Traffic Server and does not apply to the run
time heartbeat checking.
.INDENT 0.0
.TP
.B proxy.config.cop.active_health_checks
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
3.UNINDENT
Specifies which, if any, of \fBtraffic_server\fP and
\fBtraffic_manager\fP that \fBtraffic_cop\fP is allowed to kill
in the event of failed health checks. The possible values are:
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Description
T}
_
T{
\fB0\fP
T}	T{
\fBtraffic_cop\fP is not allowed to kill any processes.
T}
_
T{
\fB1\fP
T}	T{
Only \fBtraffic_manager\fP can be killed on failed health checks.
T}
_
T{
\fB2\fP
T}	T{
Only \fBtraffic_server\fP can be killed on failed health checks.
T}
_
T{
\fB3\fP
T}	T{
\fBtraffic_server\fP and \fBtraffic_manager\fP can be killed
on failures (default).
T}
_
.TE
.INDENT 0.0
.TP
.B proxy.config.output.logfile
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
traffic.out.UNINDENT
The name and location of the file that contains warnings, status messages, and error messages produced by the Traffic Server
processes. If no path is specified, then Traffic Server creates the file in its logging directory.
.INDENT 0.0
.TP
.B proxy.config.output.logfile.rolling_enabled
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.UNINDENT
Specifies how the output log is rolled. You can specify the following values:
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Description
T}
_
T{
\fB0\fP
T}	T{
Disables output log rolling.
T}
_
T{
\fB1\fP
T}	T{
Enables output log rolling at specific intervals (specified with the
\fI\%proxy.config.output.logfile.rolling_interval_sec\fP variable).
The clock starts ticking on Traffic Server boot.
T}
_
T{
\fB2\fP
T}	T{
Enables output log rolling when the output log reaches a specific size
(specified with \fI\%proxy.config.output.logfile.rolling_size_mb\fP).
T}
_
.TE
.INDENT 0.0
.TP
.B proxy.config.output.logfile.rolling_interval_sec
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
3600.TP
.B Metric
seconds.TP
.B Reloadable
Yes.UNINDENT
Specifies how often the output log is rolled, in seconds. The timer starts on Traffic Server bootup.
.INDENT 0.0
.TP
.B proxy.config.output.logfile.rolling_size_mb
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
100.TP
.B Metric
megabytes.TP
.B Reloadable
Yes.UNINDENT
Specifies at what size to roll the output log at.
.INDENT 0.0
.TP
.B proxy.config.snapshot_dir
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
snapshots.UNINDENT
The directory in which Traffic Server stores configuration
snapshots on the local system. Unless you specify an absolute
path, this directory is located in the Traffic Server \fBSYSCONFDIR\fP
directory.
.SS Thread Variables
.INDENT 0.0
.TP
.B proxy.config.exec_thread.autoconfig
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.UNINDENT
When enabled (the default, \fB1\fP), Traffic Server scales threads according to the
available CPU cores. See the config option below.
.INDENT 0.0
.TP
.B proxy.config.exec_thread.autoconfig.scale
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
FLOAT.TP
.B Default
1.5.UNINDENT
Factor by which Traffic Server scales the number of threads. The multiplier is usually
the number of available CPU cores. By default this is scaling factor is
\fB1.5\fP\&.
.INDENT 0.0
.TP
.B proxy.config.exec_thread.limit
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
2.UNINDENT
The number of threads Traffic Server will create if \fIproxy.config.exec_thread.autoconfig\fP
is set to \fB0\fP, otherwise this option is ignored.
.INDENT 0.0
.TP
.B proxy.config.accept_threads
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.UNINDENT
The number of accept threads. If disabled (\fB0\fP), then accepts will be done
in each of the worker threads.
.INDENT 0.0
.TP
.B proxy.config.thread.default.stacksize
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1048576.UNINDENT
Default thread stack size, in bytes, for all threads (default is 1 MB).
.INDENT 0.0
.TP
.B proxy.config.exec_thread.affinity
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.UNINDENT
Bind threads to specific processing units.
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Effect
T}
_
T{
\fB0\fP
T}	T{
Assign threads to machine.
T}
_
T{
\fB1\fP
T}	T{
Assign threads to NUMA nodes [default].
T}
_
T{
\fB2\fP
T}	T{
Assign threads to sockets.
T}
_
T{
\fB3\fP
T}	T{
Assign threads to cores.
T}
_
T{
\fB4\fP
T}	T{
Assign threads to processing units.
T}
_
.TE
.sp
\fBNOTE:\fP
.INDENT 0.0
.INDENT 3.5
This option only has an affect when Traffic Server has been compiled with \fB\-\-enable\-hwloc\fP\&.
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.system.file_max_pct
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
FLOAT.TP
.B Default
0.9.UNINDENT
Set the maximum number of file handles for the traffic_server process as a percentage of the the fs.file\-max proc value in Linux. The default is 90%.
.INDENT 0.0
.TP
.B proxy.config.crash_log_helper
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
traffic_crashlog.UNINDENT
This option directs \fBtraffic_server\fP to spawn a crash
log helper at startup. The value should be the path to an
executable program. If the path is not absolute, it is located
relative to configured \fBbin\fP directory.  Any user\-provided
program specified here must behave in a fashion compatible with
\fBtraffic_crashlog\fP\&. Specifically, it must implement
the \fItraffic_crashlog \-\-wait\fP behavior.
.sp
This setting not reloadable because the helper must be spawned
before \fBtraffic_server\fP drops privilege. If this variable
is set to \fBNULL\fP, no helper will be spawned.
.INDENT 0.0
.TP
.B proxy.config.restart.active_client_threshold
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.UNINDENT
This setting specifies the number of active client connections
for use by \fItraffic_ctl server restart \-\-drain\fP\&.
.SH NETWORK
.INDENT 0.0
.TP
.B proxy.config.net.connections_throttle
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
30000.UNINDENT
The total number of client and origin server connections that the server
can handle simultaneously. This is in fact the max number of file
descriptors that the \fBtraffic_server\fP process can have open at any
given time. Roughly 10% of these connections are reserved for origin server
connections, i.e. from the default, only ~9,000 client connections can be
handled. This should be tuned according to your memory size, and expected
work load.
.INDENT 0.0
.TP
.B proxy.config.net.default_inactivity_timeout
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
86400.TP
.B Reloadable
Yes.UNINDENT
The connection inactivity timeout (in seconds) to apply when
Traffic Server detects that no inactivity timeout has been applied
by the HTTP state machine. When this timeout is applied, the
\fIproxy.process.net.default_inactivity_timeout_applied\fP metric
is incremented.
.sp
See \fIadmin\-performance\-timeouts\fP for more discussion on Traffic Server timeouts.
.INDENT 0.0
.TP
.B proxy.config.net.inactivity_check_frequency
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.UNINDENT
How frequent (in seconds) to check for inactive connections. If you deal
with a lot of concurrent connections, increasing this setting can reduce
pressure on the system.
.INDENT 0.0
.TP
.B proxy.local.incoming_ip_to_bind
.UNINDENT
.INDENT 0.0
.TP
.B Scope
LOCAL.TP
.B Type
STRING.TP
.B Default
0.0.0.0 [::].UNINDENT
Controls the global default IP addresses to which to bind proxy server
ports. The value is a space separated list of IP addresses, one per
supported IP address family (currently IPv4 and IPv6).
.sp
Unless explicitly specified in \fI\%proxy.config.http.server_ports\fP, the
server port will be bound to one of these addresses, selected by IP address
family. The built in default is any address. This is used if no address for
a family is specified. This setting is useful if most or all server ports
should be bound to the same address.
.sp
\fBNOTE:\fP
.INDENT 0.0
.INDENT 3.5
This is ignored for inbound transparent server ports because they must be
able to accept connections on arbitrary IP addresses.
.UNINDENT
.UNINDENT
.SS Example
.sp
Set the global default for IPv4 to \fB192.168.101.18\fP and leave the global
default for IPv6 as any address:
.INDENT 0.0
.INDENT 3.5
.sp
.nf
.ft C
LOCAL proxy.local.incoming_ip_to_bind STRING 192.168.101.18
.ft P
.fi
.UNINDENT
.UNINDENT
.SS Example
.sp
Set the global default for IPv4 to \fB191.68.101.18\fP and the global default
for IPv6 to \fBfc07:192:168:101::17\fP:
.INDENT 0.0
.INDENT 3.5
.sp
.nf
.ft C
LOCAL proxy.local.incoming_ip_to_bind STRING 192.168.101.18 [fc07:192:168:101::17]
.ft P
.fi
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.local.outgoing_ip_to_bind
.UNINDENT
.INDENT 0.0
.TP
.B Scope
LOCAL.TP
.B Type
STRING.TP
.B Default
0.0.0.0 [::].UNINDENT
This controls the global default for the local IP address for outbound
connections to origin servers. The value is a list of space separated IP
addresses, one per supported IP address family (currently IPv4 and IPv6).
.sp
Unless explicitly specified in \fI\%proxy.config.http.server_ports\fP, one
of these addresses, selected by IP address family, will be used as the local
address for outbound connections. This setting is useful if most or all of
the server ports should use the same outbound IP addresses.
.sp
\fBNOTE:\fP
.INDENT 0.0
.INDENT 3.5
This is ignored for outbound transparent ports as the local outbound address will be the same as the client local address.
.UNINDENT
.UNINDENT
.SS Example
.sp
Set the default local outbound IP address for IPv4 connections to \fB192.168.101.18\fP\&.:
.INDENT 0.0
.INDENT 3.5
.sp
.nf
.ft C
LOCAL proxy.local.outgoing_ip_to_bind STRING 192.168.101.18
.ft P
.fi
.UNINDENT
.UNINDENT
.SS Example
.sp
Set the default local outbound IP address to \fB192.168.101.17\fP for IPv4 and \fBfc07:192:168:101::17\fP for IPv6.:
.INDENT 0.0
.INDENT 3.5
.sp
.nf
.ft C
LOCAL proxy.local.outgoing_ip_to_bind STRING 192.168.101.17 [fc07:192:168:101::17]
.ft P
.fi
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.net.event_period
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
10.UNINDENT
How often, in milli\-seconds, to schedule IO event processing. This is
unlikely to be necessary to tune, and we discourage setting it to a value
smaller than 10ms (on Linux).
.INDENT 0.0
.TP
.B proxy.config.net.accept_period
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
10.UNINDENT
How often, in milli\-seconds, to schedule accept() processing. This is
unlikely to be necessary to tune, and we discourage setting it to a value
smaller than 10ms (on Linux).
.INDENT 0.0
.TP
.B proxy.config.net.retry_delay
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
10.TP
.B Reloadable
Yes.UNINDENT
How long to wait until we retry various events that would otherwise block
the network processing threads (e.g. locks). We discourage setting this to
a value smaller than 10ms (on Linux).
.INDENT 0.0
.TP
.B proxy.config.net.throttle_delay
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
50.TP
.B Reloadable
Yes.UNINDENT
When we trigger a throttling scenario, this how long our accept() are delayed.
.SH CLUSTER
.INDENT 0.0
.TP
.B proxy.local.cluster.type
.UNINDENT
.INDENT 0.0
.TP
.B Scope
LOCAL.TP
.B Type
INT.TP
.B Default
3.UNINDENT
Sets the clustering mode:
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Effect
T}
_
T{
\fB1\fP
T}	T{
Full\-clustering mode.
T}
_
T{
\fB2\fP
T}	T{
Management\-only mode.
T}
_
T{
\fB3\fP
T}	T{
No clustering.
T}
_
.TE
.INDENT 0.0
.TP
.B proxy.config.cluster.ethernet_interface
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
eth0.UNINDENT
The network interface to be used for cluster communication. This has to be
identical on all members of a clsuter. ToDo: Is that reasonable ?? Should
this be local"
.INDENT 0.0
.TP
.B proxy.config.cluster.rsport
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
8088.UNINDENT
The reliable service port. The reliable service port is used to send
configuration information between the nodes in a cluster. All nodes in a
cluster must use the same reliable service port.
.INDENT 0.0
.TP
.B proxy.config.cluster.threads
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.UNINDENT
The number of threads for cluster communication. On heavy clusters, the
number should be adjusted. It is recommend to use the thread CPU usage as a
reference when adjusting.
.INDENT 0.0
.TP
.B proxy.config.clustger.ethernet_interface
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
\fI*NONE*\fP.UNINDENT
Set the interface to use for cluster communications.
.INDENT 0.0
.TP
.B proxy.config.http.cache.cluster_cache_local
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Overridable
Yes.UNINDENT
This turns on the local caching of objects in cluster mode. The point of
this is to allow for popular or \fIhot\fP content to be cached on all nodes
in a cluster. Be aware that the primary way to configure this behavior is
via the \fBcache.config\fP configuration file using
\fBaction=cluster\-cache\-local\fP directives.
.sp
This particular \fI\%records.config\fP configuration can be controlled per
transaction or per remap rule. As such, it augments the
\fBcache.config\fP directives, since you can turn on the local caching
feature without complex regular expression matching.
.sp
This implies that turning this on in your global \fI\%records.config\fP is
almost never what you want; instead, you want to use this either via
e.g. \fBconf_remap.so\fP overrides for a certain remap rule, or through a
custom plugin using the appropriate APIs.
.SH LOCAL MANAGER
.INDENT 0.0
.TP
.B proxy.config.admin.synthetic_port
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
8083.UNINDENT
The synthetic healthcheck port.
.INDENT 0.0
.TP
.B proxy.config.admin.number_config_bak
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
3.UNINDENT
The maximum number of copies of rolled configuration files to keep.
.INDENT 0.0
.TP
.B proxy.config.admin.user_id
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
nobody.UNINDENT
Designates the non\-privileged account to run the \fBtraffic_server\fP
process as, which also has the effect of setting ownership of configuration
and log files.
.sp
As of version 2.1.1 if the user_id is prefixed with pound character (\fB#\fP)
the remainder of the string is considered to be a
\fI\%numeric user identifier\fP\&.
If the value is set to \fB#\-1\fP Traffic Server will not change the user during startup.
.sp
\fBIMPORTANT:\fP
.INDENT 0.0
.INDENT 3.5
Attempting to set this option to \fBroot\fP or \fB#0\fP is now forbidden, as
a measure to increase security. Doing so will cause a fatal failure upon
startup in \fBtraffic_server\fP\&. However, there are two ways to
bypass this restriction:
.INDENT 0.0
.IP \(bu 2
Specify \fB\-DBIG_SECURITY_HOLE\fP in \fBCXXFLAGS\fP during compilation.
.IP \(bu 2
Set the \fBuser_id=#\-1\fP and start trafficserver as root.
.UNINDENT
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.admin.api.restricted
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
This setting specifies whether the management API should be restricted to
root processes. If this is set to \fB0\fP, then on platforms that support
passing process credentials, non\-root processes will be allowed to make
read\-only management API calls. Any management API calls that modify server
state (eg. setting a configuration variable) will still be restricted to
root processes.
.sp
This setting is not reloadable, since it is must be applied when
program:\fItraffic_manager\fP initializes.
.INDENT 0.0
.TP
.B proxy.config.disable_configuration_modification
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.UNINDENT
This setting prevents Traffic Server from rewriting the \fI\%records.config\fP
configuration file. Dynamic configuration changes can still be made using
\fBtraffic_ctl config set\fP, but these changes will not be persisted
on service restarts or when \fItraffic_ctl config reload\fP is run.
.SH PROCESS MANAGER
.INDENT 0.0
.TP
.B proxy.config.process_manager.mgmt_port
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
8084.UNINDENT
The port used for internal communication between \fBtraffic_manager\fP
and \fBtraffic_server\fP processes.
.SH ALARM CONFIGURATION
.INDENT 0.0
.TP
.B proxy.config.alarm_email
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
\fI*NONE*\fP.TP
.B Reloadable
Yes.UNINDENT
The address to which the alarm script should send email.
.INDENT 0.0
.TP
.B proxy.config.alarm.bin
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
example_alarm_bin.sh.TP
.B Reloadable
Yes.UNINDENT
Name of the script file that can execute certain actions when
an alarm is signaled. The script is invoked with up to 4 arguments:
.INDENT 0.0
.IP \(bu 2
The alarm message.
.IP \(bu 2
The value of \fI\%proxy.config.product_name\fP\&.
.IP \(bu 2
The value of \fI\%proxy.config.admin.user_id\fP\&.
.IP \(bu 2
The value of \fI\%proxy.config.alarm_email\fP\&.
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.alarm.abs_path
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
NULL.TP
.B Reloadable
Yes.UNINDENT
The absolute path to the directory containing the alarm script.
If this is not set, the script will be located relative to
\fI\%proxy.config.bin_path\fP\&.
.INDENT 0.0
.TP
.B proxy.config.alarm.script_runtime
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
5.TP
.B Reloadable
Yes.UNINDENT
The number of seconds that Traffic Server allows the alarm script
to run before aborting it.
.SH HTTP ENGINE
.INDENT 0.0
.TP
.B proxy.config.http.server_ports
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
8080 8080:ipv6.UNINDENT
Ports used for proxying HTTP traffic.
.sp
This is a list, separated by space or comma, of port descriptors\&.
Each descriptor is a sequence of keywords and values separated by colons.
Not all keywords have values, those that do are specifically noted. Keywords
with values can have an optional \fB=\fP character separating the keyword and
value. The case of keywords is ignored. The order of keywords is irrelevant
but unspecified results may occur if incompatible options are used (noted
below). Options without values are idempotent. Options with values use the
last (right most) value specified, except for \fBip\-out\fP as detailed later.
.sp
Quick reference chart:
.TS
center;
|l|l|l|.
_
T{
Name
T}	T{
Note
T}	T{
Definition
T}
_
T{
\fInumber\fP
T}	T{
Required
T}	T{
The local port.
T}
_
T{
blind
T}	T{
T}	T{
Blind (\fBCONNECT\fP) port.
T}
_
T{
compress
T}	T{
Not Implemented
T}	T{
Compressed.
T}
_
T{
ipv4
T}	T{
Default
T}	T{
Bind to IPv4 address family.
T}
_
T{
ipv6
T}	T{
T}	T{
Bind to IPv6 address family.
T}
_
T{
ip\-in
T}	T{
Value
T}	T{
Local inbound IP address.
T}
_
T{
ip\-out
T}	T{
Value
T}	T{
Local outbound IP address.
T}
_
T{
ip\-resolve
T}	T{
Value
T}	T{
IP address resolution style.
T}
_
T{
proto
T}	T{
Value
T}	T{
List of supported session protocols.
T}
_
T{
ssl
T}	T{
T}	T{
SSL terminated.
T}
_
T{
tr\-full
T}	T{
T}	T{
Fully transparent (inbound and outbound)
T}
_
T{
tr\-in
T}	T{
T}	T{
Inbound transparent.
T}
_
T{
tr\-out
T}	T{
T}	T{
Outbound transparent.
T}
_
T{
tr\-pass
T}	T{
T}	T{
Pass through enabled.
T}
_
.TE
.INDENT 0.0
.TP
.B \fInumber\fP
Local IP port to bind. This is the port to which ATS clients will connect.
.TP
.B blind
Accept only the \fBCONNECT\fP method on this port.
.sp
Not compatible with: \fBtr\-in\fP, \fBssl\fP\&.
.TP
.B compress
Compress the connection. Retained only by inertia, should be considered "not implemented".
.TP
.B ipv4
Use IPv4. This is the default and is included primarily for completeness. This forced if the \fBip\-in\fP option is used with an IPv4 address.
.TP
.B ipv6
Use IPv6. This is forced if the \fBip\-in\fP option is used with an IPv6 address.
.TP
.B ssl
Require SSL termination for inbound connections. SSL \fImust be configured\fP for this option to provide a functional server port.
.sp
Not compatible with: \fBblind\fP\&.
.TP
.B proto
Specify the \fIsession level protocols\fP supported. These should be
separated by semi\-colons. For TLS proxy ports the default value is
all available protocols. For non\-TLS proxy ports the default is HTTP
only.
.TP
.B tr\-full
Fully transparent. This is a convenience option and is identical to specifying both \fBtr\-in\fP and \fBtr\-out\fP\&.
.sp
Not compatible with: Any option not compatible with \fBtr\-in\fP or \fBtr\-out\fP\&.
.TP
.B tr\-in
Inbound transparent. The proxy port will accept connections to any IP address on the port. To have IPv6 inbound transparent you must use this and the \fBipv6\fP option. This overrides \fI\%proxy.local.incoming_ip_to_bind\fP for this port.
.sp
Not compatible with: \fBip\-in\fP, \fBblind\fP
.TP
.B tr\-out
Outbound transparent. If ATS connects to an origin server for a transaction on this port, it will use the client\(aqs address as its local address. This overrides \fI\%proxy.local.outgoing_ip_to_bind\fP for this port.
.sp
Not compatible with: \fBip\-out\fP, \fBip\-resolve\fP
.TP
.B tr\-pass
Transparent pass through. This option is useful only for inbound transparent proxy ports. If the parsing of the expected HTTP header fails, then the transaction is switched to a blind tunnel instead of generating an error response to the client. It effectively enables \fI\%proxy.config.http.use_client_target_addr\fP for the transaction as there is no other place to obtain the origin server address.
.TP
.B ip\-in
Set the local IP address for the port. This is the address to which clients will connect. This forces the IP address family for the port. The \fBipv4\fP or \fBipv6\fP can be used but it is optional and is an error for it to disagree with the IP address family of this value. An IPv6 address \fBmust\fP be enclosed in square brackets. If this option is omitted \fI\%proxy.local.incoming_ip_to_bind\fP is used.
.sp
Not compatible with: \fBtr\-in\fP\&.
.TP
.B ip\-out
Set the local IP address for outbound connections. This is the address used by ATS locally when it connects to an origin server for transactions on this port. If this is omitted \fI\%proxy.local.outgoing_ip_to_bind\fP is used.
.sp
This option can used multiple times, once for each IP address family. The address used is selected by the IP address family of the origin server address.
.sp
Not compatible with: \fBtr\-out\fP\&.
.TP
.B ip\-resolve
Set the \fI\%host resolution style\fP for transactions on this proxy port.
.sp
Not compatible with: \fBtr\-out\fP \- this option requires a value of \fBclient;none\fP which is forced and should not be explicitly specified.
.UNINDENT
.SS Example
.sp
Listen on port 80 on any address for IPv4 and IPv6.:
.INDENT 0.0
.INDENT 3.5
.sp
.nf
.ft C
80 80:ipv6
.ft P
.fi
.UNINDENT
.UNINDENT
.SS Example
.sp
Listen transparently on any IPv4 address on port 8080, and
transparently on port 8080 on local address \fBfc01:10:10:1::1\fP
(which implies \fBipv6\fP).:
.INDENT 0.0
.INDENT 3.5
.sp
.nf
.ft C
IPv4:tr\-FULL:8080 TR\-full:IP\-in=[fc02:10:10:1::1]:8080
.ft P
.fi
.UNINDENT
.UNINDENT
.SS Example
.sp
Listen on port 8080 for IPv6, fully transparent. Set up an SSL port on 443. These ports will use the IP address from \fI\%proxy.local.incoming_ip_to_bind\fP\&.  Listen on IP address \fB192.168.17.1\fP, port 80, IPv4, and connect to origin servers using the local address \fB10.10.10.1\fP for IPv4 and \fBfc01:10:10:1::1\fP for IPv6.:
.INDENT 0.0
.INDENT 3.5
.sp
.nf
.ft C
8080:ipv6:tr\-full 443:ssl ip\-in=192.168.17.1:80:ip\-out=[fc01:10:10:1::1]:ip\-out=10.10.10.1
.ft P
.fi
.UNINDENT
.UNINDENT
.SS Example
.sp
Listen on port 9090 for TSL enabled HTTP/2 or HTTP connections, accept no other session protocols.:
.INDENT 0.0
.INDENT 3.5
.sp
.nf
.ft C
9090:proto=http2;http:ssl
.ft P
.fi
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.http.connect_ports
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
443 563.UNINDENT
The range of origin server ports that can be used for tunneling via \fBCONNECT\fP\&.
.sp
Traffic Server allows tunnels only to the specified ports. Supports both wildcards
(\fB*\fP) and ranges (e.g. \fB0\-1023\fP).
.sp
\fBNOTE:\fP
.INDENT 0.0
.INDENT 3.5
These are the ports on the \fIorigin server\fP, not Traffic Server \fI\%proxy ports\fP\&.
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.http.insert_request_via_str
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
Set how the \fBVia\fP field is handled on a request to the origin server.
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Effect
T}
_
T{
\fB0\fP
T}	T{
Do not modify or set this Via header.
T}
_
T{
\fB1\fP
T}	T{
Update the Via, with normal verbosity.
T}
_
T{
\fB2\fP
T}	T{
Update the Via, with higher verbosity.
T}
_
T{
\fB3\fP
T}	T{
Update the Via, with highest verbosity.
T}
_
.TE
.sp
\fBNOTE:\fP
.INDENT 0.0
.INDENT 3.5
The \fBVia\fP header string can be decoded with the \fI\%Via Decoder Ring\fP\&.
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.http.request_via_str
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
ApacheTrafficServer/${PACKAGE_VERSION}.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
Set the server and version string in the \fBVia\fP request header to the origin server which is inserted when the value of \fI\%proxy.config.http.insert_request_via_str\fP is not \fB0\fP\&.  Note that the actual default value is defined with \fB"ApacheTrafficServer/" PACKAGE_VERSION\fP in a C++ source code, and you must write such as \fBApacheTrafficServer/6.0.0\fP if you really set a value with the version in \fI\%records.config\fP file. If you want to hide the version, you can set this value to \fBApacheTrafficServer\fP\&.
.INDENT 0.0
.TP
.B proxy.config.http.insert_response_via_str
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
Set how the \fBVia\fP field is handled on the response to the client.
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Effect
T}
_
T{
\fB0\fP
T}	T{
Do not modify or set this via header.
T}
_
T{
\fB1\fP
T}	T{
Update the via, with normal verbosity.
T}
_
T{
\fB2\fP
T}	T{
Update the via, with higher verbosity.
T}
_
T{
\fB3\fP
T}	T{
Update the via, with highest verbosity.
T}
_
.TE
.sp
\fBNOTE:\fP
.INDENT 0.0
.INDENT 3.5
The \fBVia\fP header string can be decoded with the \fI\%Via Decoder Ring\fP\&.
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.http.response_via_str
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
ApacheTrafficServer/${PACKAGE_VERSION}.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
Set the server and version string in the \fBVia\fP response header to the client which is inserted when the value of \fI\%proxy.config.http.insert_response_via_str\fP is not \fB0\fP\&.  Note that the actual default value is defined with \fB"ApacheTrafficServer/" PACKAGE_VERSION\fP in a C++ source code, and you must write such as \fBApacheTrafficServer/6.0.0\fP if you really set a value with the version in \fI\%records.config\fP file. If you want to hide the version, you can set this value to \fBApacheTrafficServer\fP\&.
.INDENT 0.0
.TP
.B proxy.config.http.send_100_continue_response
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.UNINDENT
You can specify one of the following:
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Description
T}
_
T{
\fB0\fP
T}	T{
Traffic Server will buffer the request until the post body has been recieved and
then send the request to the origin server.
T}
_
T{
\fB1\fP
T}	T{
Immediately return a \fB100 Continue\fP from Traffic Server without waiting for
the post body.
T}
_
.TE
.INDENT 0.0
.TP
.B proxy.config.http.response_server_enabled
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
You can specify one of the following:
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Description
T}
_
T{
\fB0\fP
T}	T{
No \fBServer\fP header is added to the response.
T}
_
T{
\fB1\fP
T}	T{
The \fBServer\fP header is added according to
\fI\%proxy.config.http.response_server_str\fP\&.
T}
_
T{
\fB2\fP
T}	T{
The \fBServer\fP header is added only if the response from origin does
not have one already.
T}
_
.TE
.INDENT 0.0
.TP
.B proxy.config.http.response_server_str
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
ATS/${PACKAGE_VERSION}.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
The \fBServer\fP string that Traffic Server will insert in a response header (if
requested, see above). Note that the actual default value is defined with
\fB"ATS/" PACKAGE_VERSION\fP in the C++ source, and you must write such as
\fBATS/6.0.0\fP if you really set a value with the version in
\fI\%records.config\fP\&. If you want to hide the version, you can set this
value to \fBATS\fP\&.
.INDENT 0.0
.TP
.B proxy.config.http.insert_age_in_response
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
This option specifies whether Traffic Server should insert an \fBAge\fP header in the
response. The value is the cache\(aqs estimate of the amount of time since the
response was generated or revalidated by the origin server.
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Description
T}
_
T{
\fB0\fP
T}	T{
No \fBAge\fP header is added.
T}
_
T{
\fB1\fP
T}	T{
\fBAge\fP header is added.
T}
_
.TE
.INDENT 0.0
.TP
.B proxy.config.http.chunking_enabled
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
Specifies whether Traffic Server can generate a chunked response:
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Description
T}
_
T{
\fB0\fP
T}	T{
Never respond with chunked encoding.
T}
_
T{
\fB1\fP
T}	T{
Always respond with chunked encoding.
T}
_
T{
\fB2\fP
T}	T{
Generate a chunked response if the origin server has previously
returned HTTP/1.1.
T}
_
T{
\fB3\fP
T}	T{
Generate a chunked response if the client request is HTTP/1.1 and the
origin server has previously returned HTTP/1.1.
T}
_
.TE
.sp
\fBNOTE:\fP
.INDENT 0.0
.INDENT 3.5
If HTTP/1.1 is used, then Traffic Server can use keep\-alive connections with
pipelining to origin servers.
.sp
If HTTP/1.0 is used, then Traffic Server can use keep\-alive connections without
pipelining to origin servers.
.sp
If HTTP/0.9 is used, then Traffic Server does not use keep\-alive connections to
origin servers.
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.http.chunking.size
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
4096.TP
.B Overridable
Yes.UNINDENT
If chunked transfer encoding is enabled with \fI\%proxy.config.http.chunking_enabled\fP,
and the conditions specified by that option\(aqs setting are met by the current
request, this option determines the size of the chunks, in bytes, to use
when sending content to an HTTP/1.1 client.
.INDENT 0.0
.TP
.B proxy.config.http.send_http11_requests
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
Specifies when and how Traffic Server uses HTTP/1.1 to communicate with the origin
server.
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Description
T}
_
T{
\fB0\fP
T}	T{
Never use HTTP/1.1.
T}
_
T{
\fB1\fP
T}	T{
Always use HTTP/1.1.
T}
_
T{
\fB2\fP
T}	T{
Use HTTP/1.1 with origin connections only if the server has previously
returned HTTP/1.1.
T}
_
T{
\fB3\fP
T}	T{
If the client request is HTTP/1.1 and the origin server has previously
returned HTTP/1.1, then use HTTP/1.1 for origin server connections.
T}
_
.TE
.sp
\fBNOTE:\fP
.INDENT 0.0
.INDENT 3.5
If \fI\%proxy.config.http.use_client_target_addr\fP is set to \fB1\fP, then
options \fB2\fP and \fB3\fP for this configuration variable cause the proxy
to use the client HTTP version for upstream requests.
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.http.server_tcp_init_cwnd
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Overridable
Yes.UNINDENT
Configures the size, in packets, of the initial TCP congestion window on
sockets used by the HTTP engine. This option may only be used on operating
systems which support the \fBTCP_INIT_CWND\fP option on TCP sockets.
.INDENT 0.0
.TP
.B proxy.config.http.auth_server_session_private
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.UNINDENT
If enabled (\fB1\fP) anytime a request contains a \fBAuthorization\fP,
\fBProxy\-Authorization\fP, or \fBWww\-Authenticate\fP header the connection will
be closed and not reused. This marks the connection as private. When disabled
(\fB0\fP) the connection will be available for reuse.
.INDENT 0.0
.TP
.B proxy.config.http.server_session_sharing.match
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
both.UNINDENT
Enable and set the ability to re\-use server connections across client
connections. The valid values are:
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Description
T}
_
T{
\fBnone\fP
T}	T{
Do not match and do not re\-use server sessions. If using this in
\fIts\-overridable\-config\fP (like the \fIadmin\-plugins\-conf\-remap\fP),
use the integer \fB0\fP instead.
T}
_
T{
\fBboth\fP
T}	T{
Re\-use server sessions, if \fIboth\fP the IP address and fully qualified
domain name match. If using this in \fIts\-overridable\-config\fP (like
the \fIadmin\-plugins\-conf\-remap\fP), use the integer \fB1\fP instead.
T}
_
T{
\fBip\fP
T}	T{
Re\-use server sessions, checking only that the IP address and port
of the origin server matches. If using this in
\fIts\-overridable\-config\fP (like the \fIadmin\-plugins\-conf\-remap\fP),
use the integer \fB2\fP instead.
T}
_
T{
\fBhost\fP
T}	T{
Re\-use server sessions, checking only that the fully qualified
domain name matches. If using this in \fIts\-overridable\-config\fP
(like the \fIadmin\-plugins\-conf\-remap\fP), use the integer \fB3\fP instead.
T}
_
.TE
.sp
It is strongly recommended to use either \fBnone\fP or \fBboth\fP for this value
unless you have a specific need for the other settings. The most common
reason is virtual hosts that share an IP address in which case performance
can be enhanced if those sessions can be re\-used. However, not all web
servers support requests for different virtual hosts on the same connection
so use with caution.
.sp
\fBNOTE:\fP
.INDENT 0.0
.INDENT 3.5
Server sessions to different ports never match even if the FQDN and IP
address match.
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.http.server_session_sharing.pool
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
thread.UNINDENT
Control the scope of server session re\-use if it is enabled by
\fI\%proxy.config.http.server_session_sharing.match\fP\&. Valid values are:
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Description
T}
_
T{
\fBglobal\fP
T}	T{
Re\-use sessions from a global pool of all server sessions.
T}
_
T{
\fBthread\fP
T}	T{
Re\-use sessions from a per\-thread pool.
T}
_
.TE
.INDENT 0.0
.TP
.B proxy.config.http.attach_server_session_to_client
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Overridable
Yes.UNINDENT
Control the re\-use of an server session by a user agent (client) session.
.sp
If a user agent performs more than one HTTP transaction on its connection to Traffic Server a server session must be
obtained for the second (and subsequent) transaction as for the first. This settings affects how that server session
is selected.
.sp
If this setting is \fB0\fP then after the first transaction the server session for that transaction is released to the
server pool (if any). When a server session is needed for subsequent transactions one is selected from the server
pool or created if there is no suitable server session in the pool.
.sp
If this setting is not \fB0\fP then the current server session for the user agent session is "sticky". It will be
preferred to any other server session (either from the pool or newly created). The server session will be detached
from the user agent session only if it cannot be used for the transaction. This is determined by the
\fI\%proxy.config.http.server_session_sharing.match\fP value. If the server session matches the next transaction
according to this setting then it will be used, otherwise it will be released to the pool and a different session
selected or created.
.INDENT 0.0
.TP
.B proxy.config.http.record_heartbeat
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.UNINDENT
Enables (\fB1\fP) or disables (\fB0\fP) \fBtraffic_cop\fP heartbeat logging.
.INDENT 0.0
.TP
.B proxy.config.http.use_client_target_addr
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
For fully transparent ports use the same origin server address as the client.
.sp
This option causes Traffic Server to avoid where possible doing DNS lookups in forward
transparent proxy mode. The option is only effective if the following three
conditions are true:
.INDENT 0.0
.IP \(bu 2
Traffic Server is in forward proxy mode.
.IP \(bu 2
The proxy port is inbound transparent.
.IP \(bu 2
The target URL has not been modified by either remapping or a plugin.
.UNINDENT
.sp
If any of these conditions are not true, then normal DNS processing is done
for the connection.
.sp
There are three valid values.
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Description
T}
_
T{
\fB0\fP
T}	T{
Disables the feature.
T}
_
T{
\fB1\fP
T}	T{
Enables the feature with address verification. The proxy does the
regular DNS processing. If the client\-specified origin address is not
in the set of addresses found by the proxy, the request continues to
the client specified address, but the result is not cached.
T}
_
T{
\fB2\fP
T}	T{
Enables the feature with no address verification. No DNS processing is
performed. The result is cached (if allowed otherwise). This option is
vulnerable to cache poisoning if an incorrect \fBHost\fP header is
specified, so this option should be used with extreme caution.  See
bug \fI\%TS\-2954\fP for details.
T}
_
.TE
.sp
If all of these conditions are met, then the origin server IP address is
retrieved from the original client connection, rather than through HostDB or
DNS lookup. In effect, client DNS resolution is used instead of Traffic Server DNS.
.sp
This can be used to be a little more efficient (looking up the target once
by the client rather than by both the client and Traffic Server) but the primary use
is when client DNS resolution can differ from that of Traffic Server\&. Two known uses
cases are:
.INDENT 0.0
.IP 1. 3
Embedded IP addresses in a protocol with DNS load sharing. In this case,
even though Traffic Server and the client both make the same request to the same
DNS resolver chain, they may get different origin server addresses. If
the address is embedded in the protocol then the overall exchange will
fail. One current example is Microsoft Windows update, which presumably
embeds the address as a security measure.
.IP 2. 3
The client has access to local DNS zone information which is not
available to Traffic Server\&. There are corporate nets with local DNS information
for internal servers which, by design, is not propagated outside the core
corporate network. Depending a network topology it can be the case that
Traffic Server can access the servers by IP address but cannot resolve such
addresses by name. In such as case the client supplied target address
must be used.
.UNINDENT
.sp
This solution must be considered interim. In the longer term, it should be
possible to arrange for much finer grained control of DNS lookup so that
wildcard domain can be set to use Traffic Server or client resolution. In both known
use cases, marking specific domains as client determined (rather than a
single global switch) would suffice. It is possible to do this crudely with
this flag by enabling it and then use identity URL mappings to re\-disable it
for specific domains.
.INDENT 0.0
.TP
.B proxy.config.http.keep_alive_enabled_in
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.TP
.B Overridable
Yes.UNINDENT
Enables (\fB1\fP) or disables (\fB0\fP) incoming keep\-alive connections.
.INDENT 0.0
.TP
.B proxy.config.http.keep_alive_enabled_out
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.TP
.B Overridable
Yes.UNINDENT
Enables (\fB1\fP) or disables (\fB0\fP) outgoing keep\-alive connections.
.sp
\fBNOTE:\fP
.INDENT 0.0
.INDENT 3.5
Enabling keep\-alive does not automatically enable purging of keep\-alive
requests when nearing the connection limit, that is controlled by
\fI\%proxy.config.http.server_max_connections\fP\&.
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.http.keep_alive_post_out
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.TP
.B Overridable
Yes.UNINDENT
Controls wether new POST requests re\-use keep\-alive sessions (\fB1\fP) or
create new connections per request (\fB0\fP).
.INDENT 0.0
.TP
.B proxy.config.http.disallow_post_100_continue
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
Allows you to return a 405 Method Not Supported with Posts also
containing an Expect: 100\-continue.
.sp
When a Post w/ Expect: 100\-continue is blocked the stat
proxy.process.http.disallowed_post_100_continue will be incremented.
.INDENT 0.0
.TP
.B proxy.config.http.default_buffer_size
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
8.UNINDENT
Configures the default buffer size, in bytes, to allocate for incoming
request bodies which lack a \fBContent\-length\fP header.
.INDENT 0.0
.TP
.B proxy.config.http.default_buffer_water_mark
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
32768.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.http.request_header_max_size
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
131072.UNINDENT
Controls the maximum size, in bytes, of an HTTP header in requests. Headers
in a request which exceed this size will cause the entire request to be
treated as invalid and rejected by the proxy.
.INDENT 0.0
.TP
.B proxy.config.http.response_header_max_size
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
131072.UNINDENT
Controls the maximum size, in bytes, of headers in HTTP responses from the
proxy. Any responses with a header exceeding this limit will be treated as
invalid and a client error will be returned instead.
.INDENT 0.0
.TP
.B proxy.config.http.global_user_agent_header
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
null.TP
.B Overridable
Yes.UNINDENT
An arbitrary string value that, if set, will be used to replace any request
\fBUser\-Agent\fP header.
.INDENT 0.0
.TP
.B proxy.config.http.strict_uri_parsing
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
Enables (\fB1\fP) or disables (\fB0\fP) Traffic Server to return a 400 Bad Request
if client\(aqs request URI includes character which is not \fI\%RFC 3986\fP compliant
.INDENT 0.0
.TP
.B proxy.config.http.errors.log_error_pages
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.TP
.B Reloadable
Yes.UNINDENT
Enables (\fB1\fP) or disables (\fB0\fP) the logging of responses to bad requests
to the error logging destination. Disabling this option prevents error
responses (such as \fB403\fPs) from appearing in the error logs. Any HTTP
response status codes equal to, or higher, than the minimum code defined by
\fBTS_HTTP_STATUS_BAD_REQUEST\fP are affected by this setting.
.SH PARENT PROXY CONFIGURATION
.INDENT 0.0
.TP
.B proxy.config.http.parent_proxy_routing_enable
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.UNINDENT
Enables (\fB1\fP) or disables (\fB0\fP) the parent caching option. Refer to \fIadmin\-hierarchical\-caching\fP\&.
.INDENT 0.0
.TP
.B proxy.config.http.parent_proxy.retry_time
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
300.TP
.B Reloadable
Yes.UNINDENT
The amount of time allowed between connection retries to a parent cache that is unavailable.
.INDENT 0.0
.TP
.B proxy.config.http.parent_proxy.fail_threshold
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
10.TP
.B Reloadable
Yes.UNINDENT
The number of times the connection to the parent cache can fail before Traffic Server considers the parent unavailable.
.INDENT 0.0
.TP
.B proxy.config.http.parent_proxy.total_connect_attempts
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
4.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
The total number of connection attempts allowed to a parent cache before Traffic Server bypasses the parent or fails the request
(depending on the \fBgo_direct\fP option in the \fBparent.config\fP file).
.INDENT 0.0
.TP
.B proxy.config.http.parent_proxy.per_parent_connect_attempts
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
2.TP
.B Reloadable
Yes.UNINDENT
The total number of connection attempts allowed per parent, if multiple parents are used.
.INDENT 0.0
.TP
.B proxy.config.http.parent_proxy.connect_attempts_timeout
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
30.TP
.B Reloadable
Yes.UNINDENT
The timeout value (in seconds) for parent cache connection attempts.
.sp
See \fIadmin\-performance\-timeouts\fP for more discussion on Traffic Server timeouts.
.INDENT 0.0
.TP
.B proxy.config.http.forward.proxy_auth_to_parent
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
Configures Traffic Server to send proxy authentication headers on to the parent cache.
.INDENT 0.0
.TP
.B proxy.config.http.no_dns_just_forward_to_parent
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.UNINDENT
Don\(aqt try to resolve DNS, forward all DNS requests to the parent. This is off (\fB0\fP) by default.
.SH HTTP CONNECTION TIMEOUTS
.INDENT 0.0
.TP
.B proxy.config.http.keep_alive_no_activity_timeout_in
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
115.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
Specifies how long Traffic Server keeps connections to clients open for a
subsequent request after a transaction ends. A value of \fB0\fP will disable
the no activity timeout.
.sp
See \fIadmin\-performance\-timeouts\fP for more discussion on Traffic Server timeouts.
.INDENT 0.0
.TP
.B proxy.config.http.keep_alive_no_activity_timeout_out
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
120.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
Specifies how long Traffic Server keeps connections to origin servers open
for a subsequent transfer of data after a transaction ends. A value of
\fB0\fP will disable the no activity timeout.
.sp
See \fIadmin\-performance\-timeouts\fP for more discussion on Traffic Server timeouts.
.INDENT 0.0
.TP
.B proxy.config.http.transaction_no_activity_timeout_in
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
30.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
Specifies how long Traffic Server keeps connections to clients open if a
transaction stalls.
.sp
See \fIadmin\-performance\-timeouts\fP for more discussion on Traffic Server timeouts.
.INDENT 0.0
.TP
.B proxy.config.http.transaction_no_activity_timeout_out
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
30.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
Specifies how long Traffic Server keeps connections to origin servers open if the transaction stalls.
.sp
See \fIadmin\-performance\-timeouts\fP for more discussion on Traffic Server timeouts.
.INDENT 0.0
.TP
.B proxy.config.websocket.no_activity_timeout
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
600.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
Specifies how long Traffic Server keeps connections open if a websocket stalls.
.sp
See \fIadmin\-performance\-timeouts\fP for more discussion on Traffic Server timeouts.
.INDENT 0.0
.TP
.B proxy.config.websocket.active_timeout
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
3600.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
The maximum amount of time Traffic Server keeps websocket connections open.
.sp
See \fIadmin\-performance\-timeouts\fP for more discussion on Traffic Server timeouts.
.INDENT 0.0
.TP
.B proxy.config.http.transaction_active_timeout_in
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
900.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
The maximum amount of time Traffic Server can remain connected to a client. If the transfer to the client is not complete before this
timeout expires, then Traffic Server closes the connection.
.sp
The value of \fB0\fP specifies that there is no timeout.
.sp
See \fIadmin\-performance\-timeouts\fP for more discussion on Traffic Server timeouts.
.INDENT 0.0
.TP
.B proxy.config.http.transaction_active_timeout_out
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
The maximum amount of time Traffic Server waits for fulfillment of a connection request to an origin server. If Traffic Server does not
complete the transfer to the origin server before this timeout expires, then Traffic Server terminates the connection request.
.sp
The default value of \fB0\fP specifies that there is no timeout.
.sp
See \fIadmin\-performance\-timeouts\fP for more discussion on Traffic Server timeouts.
.INDENT 0.0
.TP
.B proxy.config.http.accept_no_activity_timeout
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
120.TP
.B Reloadable
Yes.UNINDENT
The timeout interval in seconds before Traffic Server closes a connection that has no activity.
.sp
See \fIadmin\-performance\-timeouts\fP for more discussion on Traffic Server timeouts.
.INDENT 0.0
.TP
.B proxy.config.http.background_fill_active_timeout
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
Specifies how long Traffic Server continues a background fill before giving up and dropping the origin server connection.
.sp
See \fIadmin\-performance\-timeouts\fP for more discussion on Traffic Server timeouts.
.INDENT 0.0
.TP
.B proxy.config.http.background_fill_completed_threshold
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
FLOAT.TP
.B Default
0.0.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
The proportion of total document size already transferred when a client aborts at which the proxy continues fetching the document
from the origin server to get it into the cache (a \fBbackground fill\fP).
.SH HTTP REDIRECTION
.INDENT 0.0
.TP
.B proxy.config.http.redirection_enabled
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
This setting indicates whether Trafficserver does a redirect follow location on receiving a 3XX Redirect response from the Origin
server. The redirection attempt is transparent to the client and the client is served the final response from the redirected\-to
location.
.INDENT 0.0
.TP
.B proxy.config.http.number_of_redirections
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
This setting determines the maximum number of times Trafficserver does a redirect follow location on receiving a 3XX Redirect response
for a given client request.
.INDENT 0.0
.TP
.B proxy.config.http.redirect_host_no_port
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.UNINDENT
This setting enables Trafficserver to not include the port in the Host header in the redirect follow request for default/standard ports
(e.g. 80 for HTTP and 443 for HTTPS). Note that the port is still included in the Host header if it\(aqs non\-default.
.INDENT 0.0
.TP
.B proxy.config.http.redirect_use_orig_cache_key
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
This setting enables Trafficserver to allow using original request cache key (for example, set using a TS API) during a 3xx redirect follow.
The default behavior (0) is to use the URL specified by Location header in the 3xx response as the cache key.
.SH ORIGIN SERVER CONNECT ATTEMPTS
.INDENT 0.0
.TP
.B proxy.config.http.connect_attempts_max_retries
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
3.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
The maximum number of connection retries Traffic Server can make when the origin server is not responding.
Each retry attempt lasts for \fI\%proxy.config.http.connect_attempts_timeout\fP seconds.  Once the maximum number of retries is
reached, the origin is marked dead.  After this, the setting  \fI\%proxy.config.http.connect_attempts_max_retries_dead_server\fP
is used to limit the number of retry attempts to the known dead origin.
.INDENT 0.0
.TP
.B proxy.config.http.connect_attempts_max_retries_dead_server
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
Maximum number of connection retries Traffic Server can make while an origin is marked dead.  Typically this value is smaller than
\fI\%proxy.config.http.connect_attempts_max_retries\fP so an error is returned to the client faster and also to reduce the load on the dead origin.
The timeout interval \fI\%proxy.config.http.connect_attempts_timeout\fP in seconds is used with this setting.
.INDENT 0.0
.TP
.B proxy.config.http.server_max_connections
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.UNINDENT
Limits the number of socket connections across all origin servers to the
value specified. To disable, set to zero (\fB0\fP).
.sp
This value is used in determining when and if to prune active origin
sessions. Without this value set, connections to origins can consume all the
way up to ts:cv:\fIproxy.config.net.connections_throttle\fP connections, which
in turn can starve incoming requests from available connections.
.INDENT 0.0
.TP
.B proxy.config.http.origin_max_connections
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
Limits the number of socket connections per origin server to the value specified. To enable, set to one (\fB1\fP).
.INDENT 0.0
.TP
.B proxy.config.http.origin_max_connections_queue
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
\-1.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
Limits the number of requests to be queued when the \fI\%proxy.config.http.origin_max_connections\fP is reached.
When disabled (\fB\-1\fP) requests are will wait indefinitely for an available connection. When set to \fB0\fP all
requests past the \fI\%proxy.config.http.origin_max_connections\fP will immediately fail. When set to \fB>0\fP
ATS will queue that many requests to go to the origin, any additional requests past the limit will immediately fail.
.INDENT 0.0
.TP
.B proxy.config.http.origin_min_keep_alive_connections
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.UNINDENT
As connection to an origin server are opened, keep at least \(aqn\(aq number of connections open to that origin, even if
the connection isn\(aqt used for a long time period. Useful when the origin supports keep\-alive, removing the time
needed to set up a new connection from
the next request at the expense of added (inactive) connections. To enable, set to one (\fB1\fP).
.INDENT 0.0
.TP
.B proxy.config.http.connect_attempts_rr_retries
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
3.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
The maximum number of failed connection attempts allowed before a round\-robin entry is marked as \(aqdown\(aq if a server
has round\-robin DNS entries.
.INDENT 0.0
.TP
.B proxy.config.http.connect_attempts_timeout
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
30.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
The timeout value (in seconds) for time to first byte for an origin server
connection.
.sp
See \fIadmin\-performance\-timeouts\fP for more discussion on Traffic Server timeouts.
.INDENT 0.0
.TP
.B proxy.config.http.post_connect_attempts_timeout
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1800.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
The timeout value (in seconds) for an origin server connection when the client request is a \fBPOST\fP or \fBPUT\fP
request.
.sp
See \fIadmin\-performance\-timeouts\fP for more discussion on Traffic Server timeouts.
.INDENT 0.0
.TP
.B proxy.config.http.down_server.cache_time
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
60.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
Specifies how long (in seconds) Traffic Server remembers that an origin server was unreachable.
.INDENT 0.0
.TP
.B proxy.config.http.down_server.abort_threshold
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
10.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
The number of seconds before Traffic Server marks an origin server as unavailable after a client abandons a request
because the origin server was too slow in sending the response header.
.INDENT 0.0
.TP
.B proxy.config.http.uncacheable_requests_bypass_parent
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
When enabled (1), Traffic Server bypasses the parent proxy for a request that is not cacheable.
.SH CONGESTION CONTROL
.INDENT 0.0
.TP
.B proxy.config.http.congestion_control.enabled
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
Enables (\fB1\fP) or disables (\fB0\fP) the Congestion Control option, which configures Traffic Server to stop forwarding
HTTP requests to origin servers when they become congested. Traffic Server sends the client a message to retry the
congested origin server later. Refer to \fIusing\-congestion\-control\fP\&.
.INDENT 0.0
.TP
.B proxy.config.http.flow_control.enabled
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Overridable
Yes.UNINDENT
Transaction buffering / flow control is enabled if this is set to a non\-zero value. Otherwise no flow control is done.
.INDENT 0.0
.TP
.B proxy.config.http.flow_control.high_water
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Metric
bytes.TP
.B Overridable
Yes.UNINDENT
The high water mark for transaction buffer control. External source I/O is halted when the total buffer space in use
by the transaction exceeds this value.
.INDENT 0.0
.TP
.B proxy.config.http.flow_control.low_water
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Metric
bytes.TP
.B Overridable
Yes.UNINDENT
The low water mark for transaction buffer control. External source I/O is resumed when the total buffer space in use
by the transaction is no more than this value.
.INDENT 0.0
.TP
.B proxy.config.http.websocket.max_number_of_connections
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
\-1.TP
.B Reloadable
Yes.UNINDENT
When enabled >= (\fB0\fP), Traffic Server will enforce a maximum number of simultaneous websocket connections.
.SH NEGATIVE RESPONSE CACHING
.INDENT 0.0
.TP
.B proxy.config.http.negative_caching_enabled
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
When enabled (\fB1\fP), Traffic Server caches negative responses (such as \fB404 Not Found\fP)
when a requested page does not exist. The next time a client requests the
same page, Traffic Server serves the negative response directly from cache.
.sp
When disabled (\fB0\fP), Traffic Server will only cache the response if the response has
\fBCache\-Control\fP headers.
.sp
The following negative responses are cached by Traffic Server:
.TS
center;
|l|l|.
_
T{
HTTP Response Code
T}	T{
Description
T}
_
T{
\fB204\fP
T}	T{
No Content
T}
_
T{
\fB305\fP
T}	T{
Use Proxy
T}
_
T{
\fB400\fP
T}	T{
Bad Request
T}
_
T{
\fB403\fP
T}	T{
Forbidden
T}
_
T{
\fB404\fP
T}	T{
Not Found
T}
_
T{
\fB405\fP
T}	T{
Method Not Allowed
T}
_
T{
\fB500\fP
T}	T{
Internal Server Error
T}
_
T{
\fB501\fP
T}	T{
Not Implemented
T}
_
T{
\fB502\fP
T}	T{
Bad Gateway
T}
_
T{
\fB503\fP
T}	T{
Service Unavailable
T}
_
T{
\fB504\fP
T}	T{
Gateway Timeout
T}
_
.TE
.sp
The cache lifetime for objects cached from this setting is controlled via
\fI\%proxy.config.http.negative_caching_lifetime\fP\&.
.INDENT 0.0
.TP
.B proxy.config.http.negative_caching_lifetime
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1800.TP
.B Overridable
Yes.UNINDENT
How long (in seconds) Traffic Server keeps the negative responses  valid in cache. This value only affects negative
responses that do NOT have explicit \fBExpires:\fP or \fBCache\-Control:\fP lifetimes set by the server.
.INDENT 0.0
.TP
.B proxy.config.http.negative_revalidating_enabled
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
Enables (\fB1\fP) or disables (\fB0\fP) forcing revalidation of cached documents
when Traffic Server receives a negative (\fB5xx\fP only) response from the origin server.
.INDENT 0.0
.TP
.B proxy.config.http.negative_revalidating_lifetime
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1800.UNINDENT
How long, in seconds, to consider a stale cached document valid if during the
revalidation attempt Traffic Server receives a negative (\fB5xx\fP only) response from
the origin server.
.SH PROXY USER VARIABLES
.INDENT 0.0
.TP
.B proxy.config.http.anonymize_remove_from
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
When enabled (\fB1\fP), Traffic Server removes the \fBFrom\fP header to protect the privacy of your users.
.INDENT 0.0
.TP
.B proxy.config.http.anonymize_remove_referer
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.UNINDENT
When enabled (\fB1\fP), Traffic Server removes the \fBReferrer\fP header to protect the privacy of your site and users.
.INDENT 0.0
.TP
.B proxy.config.http.anonymize_remove_user_agent
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
When enabled (\fB1\fP), Traffic Server removes the \fBUser\-agent\fP header to protect the privacy of your site and users.
.INDENT 0.0
.TP
.B proxy.config.http.anonymize_remove_cookie
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
When enabled (\fB1\fP), Traffic Server removes the \fBCookie\fP header to protect the privacy of your site and users.
.INDENT 0.0
.TP
.B proxy.config.http.anonymize_remove_client_ip
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
When enabled (\fB1\fP), Traffic Server removes \fBClient\-IP\fP headers for more privacy.
.INDENT 0.0
.TP
.B proxy.config.http.insert_client_ip
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
When enabled (\fB1\fP), Traffic Server inserts \fBClient\-IP\fP headers to retain the client IP address.
.INDENT 0.0
.TP
.B proxy.config.http.anonymize_other_header_list
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
NULL.TP
.B Reloadable
Yes.UNINDENT
Comma separated list of headers Traffic Server should remove from outgoing requests.
.INDENT 0.0
.TP
.B proxy.config.http.insert_squid_x_forwarded_for
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
When enabled (\fB1\fP), Traffic Server adds the client IP address to the \fBX\-Forwarded\-For\fP header.
.INDENT 0.0
.TP
.B proxy.config.http.normalize_ae_gzip
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
Enable (\fB1\fP) to normalize all \fBAccept\-Encoding:\fP headers to one of the following:
.INDENT 0.0
.IP \(bu 2
\fBAccept\-Encoding: gzip\fP (if the header has \fBgzip\fP or \fBx\-gzip\fP with any \fBq\fP) \fBOR\fP
.IP \(bu 2
\fIblank\fP (for any header that does not include \fBgzip\fP)
.UNINDENT
.sp
This is useful for minimizing cached alternates of documents (e.g. \fBgzip, deflate\fP vs. \fBdeflate, gzip\fP). Enabling this option is
recommended if your origin servers use no encodings other than \fBgzip\fP\&.
.SH SECURITY
.INDENT 0.0
.TP
.B proxy.config.http.push_method_enabled
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.UNINDENT
Enables (\fB1\fP) or disables (\fB0\fP) the HTTP \fBPUSH\fP option, which allows you to deliver content directly to the cache without a user
request.
.sp
\fBIMPORTANT:\fP
.INDENT 0.0
.INDENT 3.5
If you enable this option, then you must also specify
a filtering rule in the ip_allow.config file to allow only certain
machines to push content into the cache.
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.http.max_post_size
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.UNINDENT
This feature is disabled by default with a value of (\fB0\fP), any positive
value will limit the size of post bodies. If a request is received with a
post body larger than this limit the response will be terminated with
413 \- Request Entity Too Large and logged accordingly.
.SH CACHE CONTROL
.INDENT 0.0
.TP
.B proxy.config.cache.enable_read_while_writer
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.TP
.B Reloadable
Yes.UNINDENT
Specifies when to enable the ability to read a cached object while another
connection is completing the write to cache for that same object. The goal
here is to avoid multiple origin connections for the same cacheable object
upon a cache miss. The possible values of this config are:
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Description
T}
_
T{
\fB0\fP
T}	T{
Never read while writing.
T}
_
T{
\fB1\fP
T}	T{
Always read while writing.
T}
_
T{
\fB2\fP
T}	T{
Always read while writing, but allow non\-cached \fBRange\fP requests
through to the origin server.
T}
_
.TE
.sp
The \fB2\fP option is useful to avoid delaying requests which can not easily
be satisfied by the partially written response.
.sp
Several other configuration values need to be set for this to be
usable. See \fIadmin\-configuration\-reducing\-origin\-requests\fP\&.
.INDENT 0.0
.TP
.B proxy.config.cache.read_while_writer.max_retries
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
10.TP
.B Reloadable
Yes.UNINDENT
Specifies how many retries trafficserver attempts to trigger read_while_writer on failing
to obtain the write VC mutex or until the first fragment is downloaded for the
object being downloaded. The retry duration is specified using the setting
\fI\%proxy.config.cache.read_while_writer_retry.delay\fP
.INDENT 0.0
.TP
.B proxy.config.cache.read_while_writer_retry.delay
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
50.TP
.B Reloadable
Yes.UNINDENT
Specifies the delay in msec, trafficserver waits to reattempt read_while_writer
on failing to obtain the write VC mutex or until the first fragment is downloaded
for the object being downloaded. Note that trafficserver implements a progressive
delay in reattempting, by doubling the configured duration from the third reattempt
onwards.
.INDENT 0.0
.TP
.B proxy.config.cache.force_sector_size
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.UNINDENT
Forces the use of a specific hardware sector size, e.g. 4096, for all disks.
.sp
SSDs and "advanced format” drives claim a sector size of 512; however, it is safe to force a higher
size than the hardware supports natively as we count atomicity in 512 byte increments.
.sp
4096\-sized drives formatted for Windows will have partitions aligned on 63 512\-byte sector boundaries,
so they will be unaligned. There are workarounds, but you need to do some research on your particular
drive. Some drives have a one\-time option to switch the partition boundary, while others might require
reformatting or repartitioning.
.sp
To be safe in Linux, you could just use the entire drive: \fB/dev/sdb\fP instead of \fB/dev/sdb1\fP and
Traffic Server will do the right thing. Misaligned partitions on Linux are auto\-detected.
.sp
For example: If \fB/sys/block/sda/sda1/alignment_offset\fP is non\-zero, ATS will offset reads/writes to
that disk by that alignment. If Linux knows about any existing partition misalignments, ATS will compensate.
.sp
Partitions formatted to support hardware sector size of more than 512 (e.g. 4096) will result in all
objects stored in the cache to be integral multiples of 4096 bytes, which will result in some waste for
small files.
.INDENT 0.0
.TP
.B proxy.config.http.cache.http
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
Enables (\fB1\fP) or disables (\fB0\fP) caching of HTTP requests.
.INDENT 0.0
.TP
.B proxy.config.http.cache.generation
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
\-1.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
If set to a value other than \fB\-1\fP, the value if this configuration
option is combined with the cache key at cache lookup time.
Changing this value has the effect of an instantaneous, zero\-cost
cache purge since it will cause all subsequent cache keys to
change. Since this is an overrideable configuration, it can be
used to purge the entire cache, or just a specific \fBremap.config\fP
rule.
.INDENT 0.0
.TP
.B proxy.config.http.cache.allow_empty_doc
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.TP
.B Reloadable
Yes.TP
.B Deprecated
Yes.UNINDENT
Enables (\fB1\fP) or disables (\fB0\fP) caching objects that have an empty
response body. This is particularly useful for caching 301 or 302 responses
with a \fBLocation\fP header but no document body. This only works if the
origin response also has a \fBContent\-Length\fP header.
.INDENT 0.0
.TP
.B proxy.config.http.doc_in_cache_skip_dns
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
When enabled (\fB1\fP), do not perform origin server DNS resolution if a fresh
copy of the requested document is available in the cache. This setting has
no effect if HTTP caching is disabled or if there are IP based ACLs
configured.
.sp
Note that plugins, particularly authorization plugins, which use the
\fBTS_HTTP_OS_DNS_HOOK\fP hook may require this configuration variable
to be disabled (\fB0\fP) in order to function properly. This will ensure that
the hook will be evaluated and plugin execution will occur even when there
is a fresh copy of the requested object in the cache (which would normally
allow the DNS lookup to be skipped, thus eliminating the hook evaluation).
.sp
The downside is that the performance gain by skipping otherwise unnecessary
DNS lookups is lost. Because the variable is overridable, you may retain
this performance benefit for portions of your cache which do not require the
use of \fBTS_HTTP_OS_DNS_HOOK\fP plugins, by ensuring that the setting
is first disabled within only the relevant transactions. Refer to the
documentation on \fIadmin\-plugins\-conf\-remap\fP for more information.
.INDENT 0.0
.TP
.B proxy.config.http.cache.ignore_client_no_cache
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
When enabled (\fB1\fP), Traffic Server ignores client requests to bypass the cache.
.INDENT 0.0
.TP
.B proxy.config.http.cache.ims_on_client_no_cache
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
When enabled (\fB1\fP), Traffic Server issues a conditional request to the origin server if an incoming request has a \fBNo\-Cache\fP header.
.INDENT 0.0
.TP
.B proxy.config.http.cache.ignore_server_no_cache
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
When enabled (\fB1\fP), Traffic Server ignores origin server requests to bypass the cache.
.INDENT 0.0
.TP
.B proxy.config.http.cache.cache_responses_to_cookies
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
Specifies how cookies are cached:
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Description
T}
_
T{
\fB0\fP
T}	T{
Do not cache any responses to cookies.
T}
_
T{
\fB1\fP
T}	T{
Cache for any content\-type.
T}
_
T{
\fB2\fP
T}	T{
Cache only for image types.
T}
_
T{
\fB3\fP
T}	T{
Cache for all but text content\-types.
T}
_
T{
\fB4\fP
T}	T{
Cache for all but text content\-types; except origin server response
without \fBSet\-Cookie\fP or with \fBCache\-Control: public\fP\&.
T}
_
.TE
.INDENT 0.0
.TP
.B proxy.config.http.cache.ignore_authentication
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Overridable
Yes.UNINDENT
When enabled (\fB1\fP), Traffic Server ignores \fBWWW\-Authentication\fP headers in responses \fBWWW\-Authentication\fP headers are removed and
not cached.
.INDENT 0.0
.TP
.B proxy.config.http.cache.cache_urls_that_look_dynamic
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
Enables (\fB1\fP) or disables (\fB0\fP) caching of URLs that look dynamic, i.e.: URLs that end in \fB\&.asp\fP or contain a question
mark (\fB?\fP), a semicolon (\fB;\fP), or \fBcgi\fP\&. For a full list, please refer to
\fI\%HttpTransact::url_looks_dynamic\fP
.INDENT 0.0
.TP
.B proxy.config.http.cache.enable_default_vary_headers
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.UNINDENT
Enables (\fB1\fP) or disables (\fB0\fP) caching of alternate versions of HTTP objects that do not contain the \fBVary\fP header.
.INDENT 0.0
.TP
.B proxy.config.http.cache.when_to_revalidate
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
Specifies when to revalidate content:
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Description
T}
_
T{
\fB0\fP
T}	T{
Use cache directives or heuristic (the default value).
T}
_
T{
\fB1\fP
T}	T{
Stale if heuristic.
T}
_
T{
\fB2\fP
T}	T{
Always stale (always revalidate).
T}
_
T{
\fB3\fP
T}	T{
Never stale.
T}
_
T{
\fB4\fP
T}	T{
Use cache directives or heuristic (0) unless the request has an
\fBIf\-Modified\-Since\fP header.
T}
_
.TE
.sp
If the request contains the \fBIf\-Modified\-Since\fP header, then Traffic Server always
revalidates the cached content and uses the client\(aqs \fBIf\-Modified\-Since\fP
header for the proxy request.
.INDENT 0.0
.TP
.B proxy.config.http.cache.required_headers
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
2.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
The type of headers required in a request for the request to be cacheable.
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Description
T}
_
T{
\fB0\fP
T}	T{
No headers required to make document cacheable.
T}
_
T{
\fB1\fP
T}	T{
Either the \fBLast\-Modified\fP header, or an explicit lifetime header
(\fBExpires\fP or \fBCache\-Control: max\-age\fP) is required.
T}
_
T{
\fB2\fP
T}	T{
Explicit lifetime is required, from either \fBExpires\fP or
\fBCache\-Control: max\-age\fP\&.
T}
_
.TE
.INDENT 0.0
.TP
.B proxy.config.http.cache.max_stale_age
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
604800.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
The maximum age allowed for a stale response before it cannot be cached.
.INDENT 0.0
.TP
.B proxy.config.http.cache.range.lookup
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.TP
.B Overridable
Yes.UNINDENT
When enabled (\fB1\fP), Traffic Server looks up range requests in the cache.
.INDENT 0.0
.TP
.B proxy.config.http.cache.range.write
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Overridable
Yes.UNINDENT
When enabled (\fB1\fP), Traffic Server will attempt to write (lock) the URL
to cache. This is rarely useful (at the moment), since it\(aqll only be able
to write to cache if the origin has ignored the \fBRange:\fP header. For a use
case where you know the origin will respond with a full (\fB200\fP) response,
you can turn this on to allow it to be cached.
.INDENT 0.0
.TP
.B proxy.config.http.cache.ignore_accept_mismatch
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
2.TP
.B Reloadable
Yes.UNINDENT
When enabled with a value of \fB1\fP, Traffic Server serves documents from cache with a
\fBContent\-Type:\fP header even if it does not match the \fBAccept:\fP header of the
request. If set to \fB2\fP (default), this logic only happens in the absence of a
\fBVary\fP header in the cached response (which is the recommended and safe use).
.sp
\fBNOTE:\fP
.INDENT 0.0
.INDENT 3.5
This option should only be enabled with \fB1\fP if you\(aqre having
problems with caching \fIand\fP you origin server doesn\(aqt set the \fBVary\fP
header. Alternatively, if the origin is incorrectly setting
\fBVary: Accept\fP or doesn\(aqt respond with \fB406 (Not Acceptable)\fP,
you can also enable this configuration with a \fB1\fP\&.
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.http.cache.ignore_accept_language_mismatch
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
2.TP
.B Reloadable
Yes.UNINDENT
When enabled with a value of \fB1\fP, Traffic Server serves documents from cache with a
\fBContent\-Language:\fP header even if it does not match the \fBAccept\-Language:\fP
header of the request. If set to \fB2\fP (default), this logic only happens in the absence of a
\fBVary\fP header in the cached response (which is the recommended and safe use).
.sp
\fBNOTE:\fP
.INDENT 0.0
.INDENT 3.5
This option should only be enabled with \fB1\fP if you\(aqre having
problems with caching \fIand\fP you origin server doesn\(aqt set the \fBVary\fP
header. Alternatively, if the origin is incorrectly setting
\fBVary: Accept\-Language\fP or doesn\(aqt respond with \fB406 (Not Acceptable)\fP,
you can also enable this configuration with a \fB1\fP\&.
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.http.cache.ignore_accept_encoding_mismatch
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
2.TP
.B Reloadable
Yes.UNINDENT
When enabled with a value of \fB1\fP, Traffic Server serves documents from cache with a
\fBContent\-Encoding:\fP header even if it does not match the \fBAccept\-Encoding:\fP
header of the request. If set to \fB2\fP (default), this logic only happens in the absence of a
\fBVary\fP header in the cached response (which is the recommended and safe use).
.sp
\fBNOTE:\fP
.INDENT 0.0
.INDENT 3.5
This option should only be enabled with \fB1\fP if you\(aqre having
problems with caching \fIand\fP you origin server doesn\(aqt set the \fBVary\fP
header. Alternatively, if the origin is incorrectly setting
\fBVary: Accept\-Encoding\fP or doesn\(aqt respond with \fB406 (Not Acceptable)\fP
you can also enable this configuration with a \fB1\fP\&.
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.http.cache.ignore_accept_charset_mismatch
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
2.TP
.B Reloadable
Yes.UNINDENT
When enabled with a value of \fB1\fP, Traffic Server serves documents from cache with a
\fBContent\-Type:\fP header even if it does not match the \fBAccept\-Charset:\fP header
of the request. If set to \fB2\fP (default), this logic only happens in the absence of a
\fBVary\fP header in the cached response (which is the recommended and safe use).
.sp
\fBNOTE:\fP
.INDENT 0.0
.INDENT 3.5
This option should only be enabled with \fB1\fP if you\(aqre having
problems with caching \fIand\fP you origin server doesn\(aqt set the \fBVary\fP
header. Alternatively, if the origin is incorrectly setting
\fBVary: Accept\-Charset\fP or doesn\(aqt respond with \fB406 (Not Acceptable)\fP,
you can also enable this configuration with a \fB1\fP\&.
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.http.cache.ignore_client_cc_max_age
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
When enabled (\fB1\fP), Traffic Server ignores any \fBCache\-Control:
max\-age\fP headers from the client. This technically violates the HTTP RFC,
but avoids a problem where a client can forcefully invalidate a cached object.
.INDENT 0.0
.TP
.B proxy.config.cache.max_doc_size
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
Specifies the maximum object size that will be cached. \fB0\fP is unlimited.
.INDENT 0.0
.TP
.B proxy.config.cache.min_average_object_size
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
8000.UNINDENT
Specifies the lower boundary of average object sizes in the cache and is
used in determining the number of \fIdirectory buckets\fP
to allocate for the in\-memory cache directory.
.INDENT 0.0
.TP
.B proxy.config.cache.permit.pinning
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.UNINDENT
When enabled (\fB1\fP), Traffic Server will keep certain HTTP objects in the cache for a certain time as specified in cache.config.
.INDENT 0.0
.TP
.B proxy.config.cache.hit_evacuate_percent
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
The size of the region (as a percentage of the total content storage in a \fIcache stripe\fP) in front of the
\fIwrite cursor\fP that constitutes a recent access hit for evacutating the accessed object.
.sp
When an object is accessed it can be marked for evacuation, that is to be copied over the write cursor and
thereby preserved from being overwritten. This is done if it is no more than a specific number of bytes in front of
the write cursor. The number of bytes is a percentage of the total number of bytes of content storage in the cache
stripe where the object is stored and that percentage is set by this variable.
.sp
By default, the feature is off (set to 0).
.INDENT 0.0
.TP
.B proxy.config.cache.hit_evacuate_size_limit
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Metric
bytes.UNINDENT
Limit the size of objects that are hit evacuated.
.sp
Objects larger than the limit are not hit evacuated. A value of 0 disables the limit.
.INDENT 0.0
.TP
.B proxy.config.cache.limits.http.max_alts
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
5.UNINDENT
The maximum number of alternates that are allowed for any given URL.
Disable by setting to 0.
.INDENT 0.0
.TP
.B proxy.config.cache.target_fragment_size
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1048576.UNINDENT
Sets the target size of a contiguous fragment of a file in the disk cache.
When setting this, consider that larger numbers could waste memory on slow
connections, but smaller numbers could increase (waste) seeks.
.INDENT 0.0
.TP
.B proxy.config.cache.alt_rewrite_max_size
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
4096.UNINDENT
Configures the size, in bytes, of an alternate that will be considered
small enough to trigger a rewrite of the resident alt fragment within a
write vector. For further details on cache write vectors, refer to the
developer documentation for \fBCacheVC\fP\&.
.SH RAM CACHE
.INDENT 0.0
.TP
.B proxy.config.cache.ram_cache.size
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
\-1.UNINDENT
By default the RAM cache size is automatically determined, based on
disk cache size; approximately 10 MB of RAM cache per GB of disk cache.
Alternatively, it can be set to a fixed value such as
\fB20GB\fP (21474836480)
.INDENT 0.0
.TP
.B proxy.config.cache.ram_cache_cutoff
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
4194304.UNINDENT
Objects greater than this size will not be kept in the RAM cache.
This should be set high enough to keep objects accessed frequently
in memory in order to improve performance.
\fB4MB\fP (4194304)
.INDENT 0.0
.TP
.B proxy.config.cache.ram_cache.algorithm
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
Two distinct RAM caches are supported, the default (0) being the \fBCLFUS\fP
(\fIClocked Least Frequently Used by Size\fP). As an alternative, a simpler
\fBLRU\fP (\fILeast Recently Used\fP) cache is also available, by changing this
configuration to 1.
.INDENT 0.0
.TP
.B proxy.config.cache.ram_cache.use_seen_filter
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
Enabling this option will filter inserts into the RAM cache to ensure that
they have been seen at least once.  For the \fBLRU\fP, this provides scan
resistance. Note that \fBCLFUS\fP already requires that a document have history
before it is inserted, so for \fBCLFUS\fP, setting this option means that a
document must be seen three times before it is added to the RAM cache.
.INDENT 0.0
.TP
.B proxy.config.cache.ram_cache.compress
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
The \fBCLFUS\fP RAM cache also supports an optional in\-memory compression.
This is not to be confused with \fBContent\-Encoding: gzip\fP compression.
The RAM cache compression is intended to try to save space in the RAM,
and is not visible to the User\-Agent (client).
.sp
Possible values are:
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Description
T}
_
T{
\fB0\fP
T}	T{
No compression
T}
_
T{
\fB1\fP
T}	T{
Fastlz (extremely fast, relatively low compression)
T}
_
T{
\fB2\fP
T}	T{
Libz (moderate speed, reasonable compression)
T}
_
T{
\fB3\fP
T}	T{
Liblzma (very slow, high compression)
T}
_
.TE
.sp
Compression runs on task threads. To use more cores for RAM cache
compression, increase \fI\%proxy.config.task_threads\fP\&.
.SH HEURISTIC EXPIRATION
.INDENT 0.0
.TP
.B proxy.config.http.cache.heuristic_min_lifetime
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
3600.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
The minimum amount of time, in seconds, an HTTP object without an expiration
date can remain fresh in the cache before is considered to be stale.
.INDENT 0.0
.TP
.B proxy.config.http.cache.heuristic_max_lifetime
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
86400.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
The maximum amount of time, in seconds, an HTTP object without an expiration
date can remain fresh in the cache before is considered to be stale.
.INDENT 0.0
.TP
.B proxy.config.http.cache.heuristic_lm_factor
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
FLOAT.TP
.B Default
0.10.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
The aging factor for freshness computations. Traffic Server stores an object for this
percentage of the time that elapsed since it last changed.
.INDENT 0.0
.TP
.B proxy.config.http.cache.guaranteed_min_lifetime
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
Establishes a guaranteed minimum lifetime boundary for freshness heuristics.
When heuristics are used, and the \fI\%proxy.config.http.cache.heuristic_lm_factor\fP
aging factor is applied, the final minimum age calculated will never be
lower than the value in this variable.
.INDENT 0.0
.TP
.B proxy.config.http.cache.guaranteed_max_lifetime
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
31536000.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
Establishes a guaranteed maximum lifetime boundary for freshness heuristics.
When heuristics are used, and the \fI\%proxy.config.http.cache.heuristic_lm_factor\fP
aging factor is applied, the final maximum age calculated will never be
higher than the value in this variable.
.INDENT 0.0
.TP
.B proxy.config.http.cache.fuzz.time
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.TP
.B Deprecated
Yes.UNINDENT
How often Traffic Server checks for an early refresh, during the period before the
document stale time. The interval specified must be in seconds.
.sp
\fBNOTE:\fP
.INDENT 0.0
.INDENT 3.5
Previous versions of Apache Traffic Server defaulted this to 240s. This
feature is deprecated as of ATS v6.2.0.
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.http.cache.fuzz.probability
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
FLOAT.TP
.B Default
0.0.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.TP
.B Deprecated
Yes.UNINDENT
The probability that a refresh is made on a document during the fuzz time
specified in \fI\%proxy.config.http.cache.fuzz.time\fP\&.
.sp
\fBNOTE:\fP
.INDENT 0.0
.INDENT 3.5
Previous versions of Apache Traffic Server defaulted this to 0.005 (0.5%).
This feature is deprecated as of ATS v6.2.0
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.http.cache.fuzz.min_time
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.TP
.B Deprecated
Yes.UNINDENT
Handles requests with a TTL less than \fI\%proxy.config.http.cache.fuzz.time\fP\&.
It allows for different times to evaluate the probability of revalidation
for small TTLs and big TTLs. Objects with small TTLs will start "rolling the
revalidation dice" near the \fBfuzz.min_time\fP, while objects with large TTLs
would start at \fBfuzz.time\fP\&. A logarithmic\-like function between determines
the revalidation evaluation start time (which will be between
\fBfuzz.min_time\fP and \fBfuzz.time\fP). As the object gets closer to expiring,
the window start becomes more likely. By default this setting is not enabled,
but should be enabled any time you have objects with small TTLs.
.sp
\fBNOTE:\fP
.INDENT 0.0
.INDENT 3.5
These fuzzing options are marked as deprecated as of v6.2.0, and will be
removed for v7.0.0. Instead, we recommend looking at the new
\fBproxy\-config\-http\-cache\-open\-write\-fail\-action\fP configuration and
the features around thundering heard avoidance (see
\fIcache\-basics\fP for details).
.UNINDENT
.UNINDENT
.SH DYNAMIC CONTENT & CONTENT NEGOTIATION
.INDENT 0.0
.TP
.B proxy.config.http.cache.vary_default_text
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
NULL.TP
.B Reloadable
Yes.UNINDENT
The header on which Traffic Server varies for text documents.
.sp
For example: if you specify \fBUser\-agent\fP, then Traffic Server caches
all the different user\-agent versions of documents it encounters.
.INDENT 0.0
.TP
.B proxy.config.http.cache.vary_default_images
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
NULL.TP
.B Reloadable
Yes.UNINDENT
The header on which Traffic Server varies for images.
.INDENT 0.0
.TP
.B proxy.config.http.cache.vary_default_other
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
NULL.TP
.B Reloadable
Yes.UNINDENT
The header on which Traffic Server varies for anything other than text and images.
.INDENT 0.0
.TP
.B proxy.config.http.cache.open_read_retry_time
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
10.TP
.B Reloadable
Yes.UNINDENT
.INDENT 0.0
.INDENT 3.5
The number of milliseconds a cacheable request will wait before requesting the object from cache if an equivalent request is in flight.
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.http.cache.max_open_read_retries
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
\-1.TP
.B Reloadable
Yes.UNINDENT
.INDENT 0.0
.INDENT 3.5
The number of times to attempt fetching an object from cache if there was an equivalent request in flight.
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.http.cache.max_open_write_retries
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
.INDENT 0.0
.INDENT 3.5
The number of times to attempt a cache open write upon failure to get a write lock.
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.http.cache.open_write_fail_action
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
.INDENT 0.0
.INDENT 3.5
This setting indicates the action taken on failing to obtain the cache open write lock on either a cache miss or a cache
hit stale. This typically happens when there is more than one request to the same cache object simultaneously. During such
a scenario, all but one (which goes to the origin) request is served either a stale copy or an error depending on this
setting.
.UNINDENT
.UNINDENT
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Description
T}
_
T{
\fB0\fP
T}	T{
Default. Disable cache and go to origin server.
T}
_
T{
\fB1\fP
T}	T{
Return a \fB502\fP error on a cache miss.
T}
_
T{
\fB2\fP
T}	T{
Serve stale if object\(aqs age is under
\fI\%proxy.config.http.cache.max_stale_age\fP\&. Otherwise, go to
origin server.
T}
_
T{
\fB3\fP
T}	T{
Return a \fB502\fP error on a cache miss or serve stale on a cache
revalidate if object\(aqs age is under
\fI\%proxy.config.http.cache.max_stale_age\fP\&. Otherwise, go to
origin server.
T}
_
T{
\fB4\fP
T}	T{
Return a \fB502\fP error on either a cache miss or on a revalidation.
T}
_
.TE
.SH CUSTOMIZABLE USER RESPONSE PAGES
.INDENT 0.0
.TP
.B proxy.config.body_factory.enable_customizations
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.UNINDENT
Specifies whether customizable response pages are language specific
or not:
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Description
T}
_
T{
\fB1\fP
T}	T{
Enable customizable user response pages in the default directory only.
T}
_
T{
\fB2\fP
T}	T{
Enable language\-targeted user response pages.
T}
_
T{
\fB3\fP
T}	T{
Enable host\-targeted user response pages.
T}
_
.TE
.INDENT 0.0
.TP
.B proxy.config.body_factory.enable_logging
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
Enables (\fB1\fP) or disables (\fB0\fP) logging for customizable response pages. When enabled, Traffic Server records a message in
the error log each time a customized response page is used or modified.
.INDENT 0.0
.TP
.B proxy.config.body_factory.template_sets_dir
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
etc/trafficserver/body_factory.UNINDENT
The customizable response page default directory. If this is a
relative path, Traffic Server resolves it relative to the
\fBPREFIX\fP directory.
.INDENT 0.0
.TP
.B proxy.config.body_factory.template_base
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
"".TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
A prefix for the file name to use to find an error template file. If set (not the empty string)
this value and an underscore are predended to the file name to find in the template sets
directory. See \fIbody\-factory\fP\&.
.INDENT 0.0
.TP
.B proxy.config.body_factory.response_suppression_mode
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
Specifies when Traffic Server suppresses generated response pages:
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Description
T}
_
T{
\fB0\fP
T}	T{
Never suppress generated response pages.
T}
_
T{
\fB1\fP
T}	T{
Always suppress generated response pages.
T}
_
T{
\fB2\fP
T}	T{
Suppress response pages only for intercepted traffic.
T}
_
.TE
.INDENT 0.0
.TP
.B proxy.config.http_ui_enabled
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
Specifies which http UI endpoints to allow within \fBremap.config\fP:
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Description
T}
_
T{
\fB0\fP
T}	T{
Disable all http UI endpoints.
T}
_
T{
\fB1\fP
T}	T{
Enable only cache endpoints.
T}
_
T{
\fB2\fP
T}	T{
Enable only stats endpoints.
T}
_
T{
\fB3\fP
T}	T{
Enable all http UI endpoints.
T}
_
.TE
.sp
To enable any enpoint there needs to be an entry in \fBremap.config\fP which
specifically enables it. Such a line would look like:
.INDENT 0.0
.INDENT 3.5
.sp
.nf
.ft C
map / http://{cache}
.ft P
.fi
.UNINDENT
.UNINDENT
.sp
The following are the cache endpoints:
.TS
center;
|l|l|.
_
T{
Name
T}	T{
Description
T}
_
T{
\fBcache\fP
T}	T{
UI to interact with the cache.
T}
_
.TE
.sp
The following are the stats endpoints:
.TS
center;
|l|l|.
_
T{
Name
T}	T{
Description
T}
_
T{
\fBcache\-internal\fP
T}	T{
Statistics about cache evacuation and volumes.
T}
_
T{
\fBhostdb\fP
T}	T{
Lookups against the hostdb.
T}
_
T{
\fBhttp\fP
T}	T{
HTTPSM details, this endpoint is also gated by
\fI\%proxy.config.http.enable_http_info\fP\&.
T}
_
T{
\fBnet\fP
T}	T{
Lookup and listing of open connections.
T}
_
.TE
.INDENT 0.0
.TP
.B proxy.config.http.enable_http_info
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
Enables (\fB1\fP) or disables (\fB0\fP) access to an endpoint within
\fI\%proxy.config.http_ui_enabled\fP which shows details about inflight
transactions (HttpSM).
.SH DNS
.INDENT 0.0
.TP
.B proxy.config.dns.search_default_domains
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.UNINDENT
Traffic Server can attempt to resolve unqualified hostnames by expanding to the local
domain. For example if a client makes a request to an unqualified host (e.g.
\fBhost_x\fP) and the Traffic Server local domain is \fBy.com\fP, then Traffic Server will expand
the hostname to \fBhost_x.y.com\fP\&.
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Description
T}
_
T{
\fB0\fP
T}	T{
Disable local domain expansion.
T}
_
T{
\fB1\fP
T}	T{
Enable local domain expansion.
T}
_
T{
\fB2\fP
T}	T{
Enable local domain expansion, but do not split local domain name.
T}
_
.TE
.INDENT 0.0
.TP
.B proxy.config.dns.splitDNS.enabled
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.UNINDENT
Enables (\fB1\fP) or disables (\fB0\fP) DNS server selection. When enabled, Traffic Server refers to the \fBsplitdns.config\fP file for
the selection specification. Refer to \fIConfiguring DNS Server Selection\fP\&.
.INDENT 0.0
.TP
.B proxy.config.dns.resolv_conf
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
/etc/resolv.conf.UNINDENT
Allows to specify which \fBresolv.conf\fP file to use for finding resolvers. While the format of this file must be the same as the
standard \fBresolv.conf\fP file, this option allows an administrator to manage the set of resolvers in an external configuration file,
without affecting how the rest of the operating system uses DNS.
.INDENT 0.0
.TP
.B proxy.config.dns.round_robin_nameservers
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.TP
.B Reloadable
Yes.UNINDENT
Enables (\fB1\fP) or disables (\fB0\fP) DNS server round\-robin.
.INDENT 0.0
.TP
.B proxy.config.dns.nameservers
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
NULL.TP
.B Reloadable
Yes.UNINDENT
The DNS servers.
.INDENT 0.0
.TP
.B proxy.config.srv_enabled
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
Indicates whether to use SRV records for orgin server lookup.
.INDENT 0.0
.TP
.B proxy.config.dns.dedicated_thread
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
Create and dedicate a thread entirely for DNS processing. This is probably
most useful on system which do a significant number of DNS lookups,
typically forward proxies. But even on other systems, it can avoid some
contention on the first worker thread (which otherwise takes on the burden of
all DNS lookups).
.INDENT 0.0
.TP
.B proxy.config.dns.validate_query_name
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
When enabled (1) provides additional resilience against DNS forgery (for instance
in DNS Injection attacks), particularly in forward or transparent proxies, but
requires that the resolver populates the queries section of the response properly.
.SH HOSTDB
.INDENT 0.0
.TP
.B proxy.config.hostdb.lookup_timeout
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
30.TP
.B Metric
seconds.TP
.B Reloadable
Yes.UNINDENT
Time to wait for a DNS response in seconds.
.sp
See \fIadmin\-performance\-timeouts\fP for more discussion on Traffic Server timeouts.
.INDENT 0.0
.TP
.B proxy.config.hostdb.serve_stale_for
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
\fI*NONE*\fP.TP
.B Metric
seconds.TP
.B Reloadable
Yes.UNINDENT
The number of seconds for which to use a stale NS record while initiating a
background fetch for the new data.
.sp
If not set then stale records are not served.
.INDENT 0.0
.TP
.B proxy.config.hostdb.max_size
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
10737418240.TP
.B Metric
bytes.UNINDENT
The maximum amount of space (in bytes) allocated to \fBhostdb\fP\&.
Setting this value to \fB\-1\fP will disable size limit enforcement.
.INDENT 0.0
.TP
.B proxy.config.hostdb.max_count
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
\-1.UNINDENT
The maximum number of entries that can be stored in hostdb. A value of \fB\-1\fP
disables item count limit enforcement.
.sp
\fBNOTE:\fP
.INDENT 0.0
.INDENT 3.5
For values above \fB200000\fP, you must increase \fI\%proxy.config.hostdb.max_size\fP
by at least 44 bytes per entry.
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.hostdb.ttl_mode
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.UNINDENT
A host entry will eventually time out and be discarded. This variable
controls how that time is calculated. A DNS request will return a TTL value
and an internal value can be set with \fBproxy.config.hostdb.timeout\fP\&.
This variable determines which value will be used.
.TS
center;
|l|l|.
_
T{
Value
T}	T{
TTL
T}
_
T{
\fB0\fP
T}	T{
The TTL from the DNS response.
T}
_
T{
\fB1\fP
T}	T{
The internal timeout value.
T}
_
T{
\fB2\fP
T}	T{
The smaller of the DNS and internal TTL values. The internal timeout
value becomes a maximum TTL.
T}
_
T{
\fB3\fP
T}	T{
The larger of the DNS and internal TTL values. The internal timeout
value become a minimum TTL.
T}
_
.TE
.INDENT 0.0
.TP
.B proxy.config.hostdb.fail.timeout
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
Time to live value for "failed" hostdb lookups.
.sp
\fBNOTE:\fP
.INDENT 0.0
.INDENT 3.5
HostDB considers any response that does not contain a response to
the query a failure. This means "failure" responses (such as SOA) are
subject to this timeout
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.hostdb.strict_round_robin
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.UNINDENT
Set host resolution to use strict round robin.
.sp
When this and \fI\%proxy.config.hostdb.timed_round_robin\fP are both
disabled (set to \fB0\fP), Traffic Server always uses the same origin server for the
same client, for as long as the origin server is available. Otherwise if
this is set then IP address is rotated on every request. This setting takes
precedence over \fI\%proxy.config.hostdb.timed_round_robin\fP\&.
.INDENT 0.0
.TP
.B proxy.config.hostdb.timed_round_robin
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.UNINDENT
Set host resolution to use timed round robin.
.sp
When this and \fI\%proxy.config.hostdb.strict_round_robin\fP are both
disabled (set to \fB0\fP), Traffic Server always uses the same origin server for the
same client, for as long as the origin server is available. Otherwise if
this is set to \fIN\fP the IP address is rotated if more than \fIN\fP seconds have
passed since the first time the current address was used.
.INDENT 0.0
.TP
.B proxy.config.hostdb.host_file.path
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
NULL.UNINDENT
Set the file path for an external host file.
.sp
If this is set (non\-empty) then the file is presumed to be a hosts file in
the standard \fI\%host file format\fP\&.
It is read and the entries there added to the HostDB. The file is
periodically checked for a more recent modification date in which case it is
reloaded. The interval is set with \fI\%proxy.config.hostdb.host_file.interval\fP\&.
.sp
While not technically reloadable, the value is read every time the file is
to be checked so that if changed the new value will be used on the next
check and the file will be treated as modified.
.INDENT 0.0
.TP
.B proxy.config.hostdb.host_file.interval
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
86400.TP
.B Metric
seconds.TP
.B Reloadable
Yes.UNINDENT
Set the file changed check timer for \fI\%proxy.config.hostdb.host_file.path\fP\&.
.sp
The file is checked every this many seconds to see if it has changed. If so
the HostDB is updated with the new values in the file.
.INDENT 0.0
.TP
.B proxy.config.hostdb.partitions
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
64.UNINDENT
The number of partitions for hostdb. If you are seeing lock contention within
hostdb\(aqs cache (due to a large number of records) you can increase the number
of partitions
.INDENT 0.0
.TP
.B proxy.config.hostdb.ip_resolve
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
NULL.UNINDENT
Set the host resolution style.
.sp
This is an ordered list of keywords separated by semicolons that specify how
a host name is to be resolved to an IP address. The keywords are case
insensitive.
.TS
center;
|l|l|.
_
T{
Keyword
T}	T{
Description
T}
_
T{
\fBipv4\fP
T}	T{
Resolve to an IPv4 address.
T}
_
T{
\fBipv6\fP
T}	T{
Resolve to an IPv6 address.
T}
_
T{
\fBclient\fP
T}	T{
Resolve to the same family as the client IP address.
T}
_
T{
\fBnone\fP
T}	T{
Stop resolving.
T}
_
.TE
.sp
The order of the keywords is critical. When a host name needs to be resolved
it is resolved in same order as the keywords. If a resolution fails, the
next option in the list is tried. The keyword \fBnone\fP means to give up
resolution entirely. The keyword list has a maximum length of three
keywords, more are never needed. By default there is an implicit
\fBipv4;ipv6\fP attached to the end of the string unless the keyword
\fBnone\fP appears.
.SS Example
.sp
Use the incoming client family, then try IPv4 and IPv6.
.INDENT 0.0
.INDENT 3.5
.sp
.nf
.ft C
client;ipv4;ipv6
.ft P
.fi
.UNINDENT
.UNINDENT
.sp
Because of the implicit resolution this can also be expressed as just
.INDENT 0.0
.INDENT 3.5
.sp
.nf
.ft C
client
.ft P
.fi
.UNINDENT
.UNINDENT
.SS Example
.sp
Resolve only to IPv4.
.INDENT 0.0
.INDENT 3.5
.sp
.nf
.ft C
ipv4;none
.ft P
.fi
.UNINDENT
.UNINDENT
.SS Example
.sp
Resolve only to the same family as the client (do not permit cross family transactions).
.INDENT 0.0
.INDENT 3.5
.sp
.nf
.ft C
client;none
.ft P
.fi
.UNINDENT
.UNINDENT
.sp
This value is a global default that can be overridden by \fI\%proxy.config.http.server_ports\fP\&.
.sp
\fBNOTE:\fP
.INDENT 0.0
.INDENT 3.5
This style is used as a convenience for the administrator. During a resolution the \fIresolution order\fP will be
one family, then possibly the other. This is determined by changing \fBclient\fP to \fBipv4\fP or \fBipv6\fP based on the
client IP address and then removing duplicates.
.UNINDENT
.UNINDENT
.sp
\fBIMPORTANT:\fP
.INDENT 0.0
.INDENT 3.5
This option has no effect on outbound transparent connections The local IP address used in the connection to the
origin server is determined by the client, which forces the IP address family of the address used for the origin
server. In effect, outbound transparent connections always use a resolution style of "\fBclient\fP".
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.hostdb.verify_after
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
720.UNINDENT
Set the interval (in seconds) in which to re\-query DNS regardless of TTL status.
.INDENT 0.0
.TP
.B proxy.config.hostdb.filename
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
"host.db".UNINDENT
The filename to persist hostdb to on disk.
.INDENT 0.0
.TP
.B proxy.config.cache.hostdb.sync_frequency
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
120.UNINDENT
Set the frequency (in seconds) to sync hostdb to disk.
.sp
Note: hostdb is syncd to disk on a per\-partition basis (of which there are 64).
This means that the minumum time to sync all data to disk is \fI\%proxy.config.cache.hostdb.sync_frequency\fP * 64
.SH LOGGING CONFIGURATION
.INDENT 0.0
.TP
.B proxy.config.log.logging_enabled
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
3.TP
.B Reloadable
Yes.UNINDENT
Enables and disables event logging:
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Effect
T}
_
T{
\fB0\fP
T}	T{
Logging disabled.
T}
_
T{
\fB1\fP
T}	T{
Log errors only.
T}
_
T{
\fB2\fP
T}	T{
Log transactions only.
T}
_
T{
\fB3\fP
T}	T{
Dull logging (errors and transactions).
T}
_
.TE
.sp
Refer to \fIadmin\-monitoring\-logging\fP for more information on event logging.
.INDENT 0.0
.TP
.B proxy.config.log.max_secs_per_buffer
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
5.TP
.B Reloadable
Yes.UNINDENT
The maximum amount of time before data in the buffer is flushed to disk.
.INDENT 0.0
.TP
.B proxy.config.log.max_space_mb_for_logs
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
25000.TP
.B Metric
megabytes.TP
.B Reloadable
Yes.UNINDENT
The amount of space allocated to the logging directory (in MB).
The headroom amount specified by
\fI\%proxy.config.log.max_space_mb_headroom\fP is taken from
this space allocation.
.sp
\fBNOTE:\fP
.INDENT 0.0
.INDENT 3.5
All files in the logging directory contribute to the space used,
even if they are not log files. In collation client mode, if
there is no local disk logging, or
\fI\%proxy.config.log.max_space_mb_for_orphan_logs\fP is set
to a higher value than \fI\%proxy.config.log.max_space_mb_for_logs\fP,
Traffic Server will take \fI\%proxy.config.log.max_space_mb_for_orphan_logs\fP
for maximum allowed log space.
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.log.max_space_mb_for_orphan_logs
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
25.TP
.B Metric
megabytes.TP
.B Reloadable
Yes.UNINDENT
The amount of space allocated to the logging directory (in MB) if this node is acting as a collation client.
.sp
\fBNOTE:\fP
.INDENT 0.0
.INDENT 3.5
When max_space_mb_for_orphan_logs is take as the maximum allowed log space in the logging system, the same rule apply
to proxy.config.log.max_space_mb_for_logs also apply to proxy.config.log.max_space_mb_for_orphan_logs, ie: All files
in the logging directory contribute to the space used, even if they are not log files. you may need to consider this
when you enable full remote logging, and bump to the same size as proxy.config.log.max_space_mb_for_logs.
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.log.max_space_mb_headroom
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1000.TP
.B Metric
megabytes.TP
.B Reloadable
Yes.UNINDENT
The tolerance for the log space limit (in megabytes). If the variable \fI\%proxy.config.log.auto_delete_rolled_files\fP is set to \fB1\fP
(enabled), then autodeletion of log files is triggered when the amount of free space available in the logging directory is less than
the value specified here.
.INDENT 0.0
.TP
.B proxy.config.log.hostname
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
localhost.TP
.B Reloadable
Yes.UNINDENT
The hostname of the machine running Traffic Server.
.INDENT 0.0
.TP
.B proxy.config.log.logfile_dir
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
var/log/trafficserver.TP
.B Reloadable
Yes.UNINDENT
The path to the logging directory. This can be an absolute path
or a path relative to the \fBPREFIX\fP directory in which Traffic
Server is installed.
.sp
\fBNOTE:\fP
.INDENT 0.0
.INDENT 3.5
The directory you specify must already exist.
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.log.logfile_perm
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
rw\-r\-\-r\-\-.TP
.B Reloadable
Yes.UNINDENT
The log file permissions. The standard UNIX file permissions are used (owner, group, other). Permissible values are:
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Description
T}
_
T{
\fB\-\fP
T}	T{
No permissions.
T}
_
T{
\fBr\fP
T}	T{
Read permission.
T}
_
T{
\fBw\fP
T}	T{
Write permission.
T}
_
T{
\fBx\fP
T}	T{
Execute permission.
T}
_
.TE
.sp
Permissions are subject to the umask settings for the Traffic Server process. This
means that a umask setting of \fB002\fP will not allow write permission for
others, even if specified in the configuration file. Permissions for
existing log files are not changed when the configuration is modified.
.INDENT 0.0
.TP
.B proxy.local.log.collation_mode
.UNINDENT
.INDENT 0.0
.TP
.B Scope
LOCAL.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.UNINDENT
Set the log collation mode.
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Effect
T}
_
T{
\fB0\fP
T}	T{
Log collation is disabled.
T}
_
T{
\fB1\fP
T}	T{
This host is a log collation server.
T}
_
T{
\fB2\fP
T}	T{
This host is a collation client and sends entries using standard
formats to the collation server.
T}
_
T{
\fB3\fP
T}	T{
This host is a collation client and sends entries using the
traditional custom formats to the collation server.
T}
_
T{
\fB4\fP
T}	T{
This host is a collation client and sends entries that use both the
standard and traditional custom formats to the collation server.
T}
_
.TE
.sp
For information on sending custom formats to the collation server,
refer to \fIadmin\-monitoring\-logging\-formats\fP and \fBlogging.config\fP\&.
.sp
\fBNOTE:\fP
.INDENT 0.0
.INDENT 3.5
Although Traffic Server supports traditional custom logging, you should use
the more versatile XML\-based custom formats.
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.log.collation_host
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
NULL.UNINDENT
The hostname of the log collation server.
.INDENT 0.0
.TP
.B proxy.config.log.collation_port
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
8085.TP
.B Reloadable
Yes.UNINDENT
The port used for communication between the collation server and client.
.INDENT 0.0
.TP
.B proxy.config.log.collation_secret
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
foobar.TP
.B Reloadable
Yes.UNINDENT
The password used to validate logging data and prevent the exchange of unauthorized information when a collation server is being used.
.INDENT 0.0
.TP
.B proxy.config.log.collation_host_tagged
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.UNINDENT
When enabled (\fB1\fP), configures Traffic Server to include the hostname of the collation client that generated the log entry in each entry.
.INDENT 0.0
.TP
.B proxy.config.log.collation_retry_sec
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
5.TP
.B Reloadable
Yes.UNINDENT
The number of seconds between collation server connection retries.
.INDENT 0.0
.TP
.B proxy.config.log.collation_host_timeout
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
86390.UNINDENT
The number of seconds before inactivity time\-out events for the host side.
This setting over\-rides the default set with proxy.config.net.default_inactivity_timeout
for log collation connections.
.sp
The default is set for 10s less on the host side to help prevent any possible race
conditions. If the host disconnects first, the client will see the disconnect
before its own time\-out and re\-connect automatically. If the client does not see
the disconnect, i.e., connection is "locked\-up" for some reason, it will disconnect
when it reaches its own time\-out and then re\-connect automatically.
.INDENT 0.0
.TP
.B proxy.config.log.collation_client_timeout
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
86400.UNINDENT
The number of seconds before inactivity time\-out events for the client side.
This setting over\-rides the default set with proxy.config.net.default_inactivity_timeout
for log collation connections.
.INDENT 0.0
.TP
.B proxy.config.log.rolling_enabled
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.TP
.B Reloadable
Yes.UNINDENT
Specifies how log files are rolled. You can specify the following values:
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Description
T}
_
T{
\fB0\fP
T}	T{
Disables log file rolling.
T}
_
T{
\fB1\fP
T}	T{
Enables log file rolling at specific intervals during the day
(specified with the \fI\%proxy.config.log.rolling_interval_sec\fP and
\fI\%proxy.config.log.rolling_offset_hr\fP variables).
T}
_
T{
\fB2\fP
T}	T{
Enables log file rolling when log files reach a specific size
(specified with \fI\%proxy.config.log.rolling_size_mb\fP).
T}
_
T{
\fB3\fP
T}	T{
Enables log file rolling at specific intervals during the day or when
log files reach a specific size (whichever occurs first).
T}
_
T{
\fB4\fP
T}	T{
Enables log file rolling at specific intervals during the day when log
files reach a specific size (i.e. at a specified time if the file is
of the specified size).
T}
_
.TE
.INDENT 0.0
.TP
.B proxy.config.log.rolling_interval_sec
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
86400.TP
.B Reloadable
Yes.UNINDENT
The log file rolling interval, in seconds. The minimum value is \fB60\fP (1 minute). The maximum, and default, value is 86400 seconds (one day).
.sp
\fBNOTE:\fP
.INDENT 0.0
.INDENT 3.5
If you start Traffic Server within a few minutes of the next rolling time, then rolling might not occur until the next rolling time.
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.log.rolling_offset_hr
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.UNINDENT
The file rolling offset hour. The hour of the day that starts the log rolling period.
.INDENT 0.0
.TP
.B proxy.config.log.rolling_size_mb
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
10.TP
.B Reloadable
Yes.UNINDENT
The size, in megabytes, that log files must reach before rolling takes place.
The minimum value for this setting is \fB10\fP\&.
.INDENT 0.0
.TP
.B proxy.config.log.auto_delete_rolled_files
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.TP
.B Reloadable
Yes.UNINDENT
Enables (\fB1\fP) or disables (\fB0\fP) automatic deletion of rolled files.
.INDENT 0.0
.TP
.B proxy.config.log.sampling_frequency
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.TP
.B Reloadable
Yes.UNINDENT
Configures Traffic Server to log only a sample of transactions rather than every
transaction. You can specify the following values:
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Description
T}
_
T{
\fB1\fP
T}	T{
Log every transaction.
T}
_
T{
\fB2\fP
T}	T{
Log every second transaction.
T}
_
T{
\fB3\fP
T}	T{
Log every third transaction.
T}
_
T{
\fIn\fP
T}	T{
\&... and so on...
T}
_
.TE
.INDENT 0.0
.TP
.B proxy.config.log.periodic_tasks_interval
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
5.TP
.B Metric
seconds.TP
.B Reloadable
Yes.UNINDENT
How often Traffic Server executes log related periodic tasks, in seconds
.INDENT 0.0
.TP
.B proxy.config.http.slow.log.threshold
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Metric
milliseconds.TP
.B Reloadable
Yes.UNINDENT
If set to a non\-zero value \fIN\fP then any connection that takes longer than \fIN\fP milliseconds from accept to
completion will cause its timing stats to be written to the \fI\%debugging log file\fP\&. This is identifying data about the transaction and all of the \fBtransaction milestones\fP\&.
.INDENT 0.0
.TP
.B proxy.config.log.config.filename
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
logging.config.TP
.B Reloadable
Yes.UNINDENT
This configuration value specifies the path to the
\fBlogging.config\fP configuration file. If this is a relative
path, Traffic Server loads it relative to the \fBSYSCONFDIR\fP directory.
.SH DIAGNOSTIC LOGGING CONFIGURATION
.INDENT 0.0
.TP
.B proxy.config.diags.output.diag
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
E.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.diags.output.debug
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
E.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.diags.output.status
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
L.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.diags.output.note
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
L.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.diags.output.warning
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
L.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.diags.output.error
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
SL.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.diags.output.fatal
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
SL.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.diags.output.alert
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
L.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.diags.output.emergency
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
SL.UNINDENT
The diagnosic output configuration variables control where Traffic
Server should log diagnostic output. Messages at each diagnostic level
can be directed to any combination of diagnostic destinations.
Valid diagnostic message destinations are:
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Description
T}
_
T{
\fBO\fP
T}	T{
Log to standard output.
T}
_
T{
\fBE\fP
T}	T{
Log to standard error.
T}
_
T{
\fBS\fP
T}	T{
Log to syslog.
T}
_
T{
\fBL\fP
T}	T{
Log to \fBdiags.log\fP\&.
T}
_
.TE
.SS Example
.sp
To log debug diagnostics to both syslog and \fIdiags.log\fP:
.INDENT 0.0
.INDENT 3.5
.sp
.nf
.ft C
CONFIG proxy.config.diags.output.debug STRING SL
.ft P
.fi
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.diags.show_location
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.UNINDENT
Annotates diagnostic messages with the source code location. Set to 1 to enable
for Debug() messages only. Set to 2 to enable for all messages.
.INDENT 0.0
.TP
.B proxy.config.diags.debug.enabled
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
Enables logging for diagnostic messages whose log level is \fIdiag\fP or \fIdebug\fP\&.
.INDENT 0.0
.TP
.B proxy.config.diags.debug.tags
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
http.*|dns.*.UNINDENT
Each Traffic Server \fIdiag\fP and \fIdebug\fP level message is annotated with a subsytem tag.
This configuration contains a regular expression that filters the messages
based on the tag. Some commonly used debug tags are:
.TS
center;
|l|l|.
_
T{
Tag
T}	T{
Subsytem usage
T}
_
T{
dns
T}	T{
DNS query resolution
T}
_
T{
http_hdrs
T}	T{
Logs the headers for HTTP requests and responses
T}
_
T{
privileges
T}	T{
Privilege elevation
T}
_
T{
ssl
T}	T{
TLS termination and certificate processing
T}
_
.TE
.sp
Traffic Server plugins will typically log debug messages using the \fBTSDebug()\fP
API, passing the plugin name as the debug tag.
.INDENT 0.0
.TP
.B proxy.config.diags.logfile.rolling_enabled
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.UNINDENT
Specifies how the diagnostics log is rolled. You can specify the following values:
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Description
T}
_
T{
\fB0\fP
T}	T{
Disables diagnostics log rolling.
T}
_
T{
\fB1\fP
T}	T{
Enables diagnostics log rolling at specific intervals (specified with
\fI\%proxy.config.diags.logfile.rolling_interval_sec\fP). The "clock"
starts ticking on Traffic Server startup.
T}
_
T{
\fB2\fP
T}	T{
Enables diagnostics log rolling when the diagnostics log reaches a
specific size (specified with
\fI\%proxy.config.diags.logfile.rolling_size_mb\fP).
T}
_
.TE
.INDENT 0.0
.TP
.B proxy.config.diags.logfile.rolling_interval_sec
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
3600.TP
.B Metric
seconds.TP
.B Reloadable
Yes.UNINDENT
Specifies how often the diagnostics log is rolled, in seconds. The timer starts on Traffic Server bootup.
.INDENT 0.0
.TP
.B proxy.config.diags.logfile.rolling_size_mb
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
100.TP
.B Metric
megabytes.TP
.B Reloadable
Yes.UNINDENT
Specifies at what size to roll the diagnostics log at.
.SH REVERSE PROXY
.INDENT 0.0
.TP
.B proxy.config.reverse_proxy.enabled
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.TP
.B Reloadable
Yes.UNINDENT
Enables (\fB1\fP) or disables (\fB0\fP) HTTP reverse proxy.
.INDENT 0.0
.TP
.B proxy.config.header.parse.no_host_url_redirect
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
NULL.TP
.B Reloadable
Yes.UNINDENT
The URL to which to redirect requests with no host headers (reverse
proxy).
.SH URL REMAP RULES
.INDENT 0.0
.TP
.B proxy.config.url_remap.filename
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
remap.config.UNINDENT
Sets the name of the \fBremap.config\fP file.
.INDENT 0.0
.TP
.B proxy.config.url_remap.remap_required
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.TP
.B Reloadable
Yes.UNINDENT
Set this variable to \fB1\fP if you want Traffic Server to serve
requests only from origin servers listed in the mapping rules of the
\fBremap.config\fP file. If a request does not match, then the browser
will receive an error.
.INDENT 0.0
.TP
.B proxy.config.url_remap.pristine_host_hdr
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.TP
.B Overridable
Yes.UNINDENT
Set this variable to \fB1\fP if you want to retain the client host
header in a request during remapping.
.SH SSL TERMINATION
.INDENT 0.0
.TP
.B proxy.config.ssl.server.cipher_suite
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
<see notes>.UNINDENT
Configures the set of encryption, digest, authentication, and key exchange
algorithms provided by OpenSSL which Traffic Server will use for SSL connections. For
the list of algorithms and instructions on constructing an appropriately
formatting cipher_suite string, see
\fI\%OpenSSL Ciphers\fP\&.
.sp
The current default, included in the \fBrecords.config.default\fP example
configuration is:
.sp
ECDHE\-ECDSA\-AES256\-GCM\-SHA384:ECDHE\-RSA\-AES256\-GCM\-SHA384:ECDHE\-ECDSA\-AES128\-GCM\-SHA256:ECDHE\-RSA\-AES128\-GCM\-SHA256:DHE\-RSA\-AES256\-GCM\-SHA384:DHE\-DSS\-AES256\-GCM\-SHA384:DHE\-RSA\-AES128\-GCM\-SHA256:DHE\-DSS\-AES128\-GCM\-SHA256:ECDHE\-ECDSA\-AES256\-SHA384:ECDHE\-RSA\-AES256\-SHA384:ECDHE\-ECDSA\-AES256\-SHA:ECDHE\-RSA\-AES256\-SHA:ECDHE\-ECDSA\-AES128\-SHA256:ECDHE\-RSA\-AES128\-SHA256:ECDHE\-ECDSA\-AES128\-SHA:ECDHE\-RSA\-AES128\-SHA:DHE\-RSA\-AES256\-SHA256:DHE\-DSS\-AES256\-SHA256:DHE\-RSA\-AES128\-SHA256:DHE\-DSS\-AES128\-SHA256:DHE\-RSA\-AES256\-SHA:DHE\-DSS\-AES256\-SHA:DHE\-RSA\-AES128\-SHA:DHE\-DSS\-AES128\-SHA:AES256\-GCM\-SHA384:AES128\-GCM\-SHA256:AES256\-SHA256:AES128\-SHA256:AES256\-SHA:AES128\-SHA:DES\-CBC3\-SHA:!aNULL:!eNULL:!EXPORT:!DES:!RC4:!MD5:!PSK:!aECDH:!EDH\-DSS\-DES\-CBC3\-SHA:!EDH\-RSA\-DES\-CBC3\-SHA:!KRB5\-DES\-CBC3\-SHA
.INDENT 0.0
.TP
.B proxy.config.ssl.TLSv1
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.UNINDENT
Enables (\fB1\fP) or disables (\fB0\fP) TLSv1.
.INDENT 0.0
.TP
.B proxy.config.ssl.TLSv1_1
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.UNINDENT
Enables (\fB1\fP) or disables (\fB0\fP) TLS v1.1.  If not specified, enabled by default.  [Requires OpenSSL v1.0.1 and higher]
.INDENT 0.0
.TP
.B proxy.config.ssl.TLSv1_2
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.UNINDENT
Enables (\fB1\fP) or disables (\fB0\fP) TLS v1.2.  If not specified, enabled by default.  [Requires OpenSSL v1.0.1 and higher]
.INDENT 0.0
.TP
.B proxy.config.ssl.client.certification_level
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
Sets the client certification level:
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Description
T}
_
T{
\fB0\fP
T}	T{
Client certificates are \fBignored\fP\&. Traffic Server does not verify client
certificates during the SSL handshake. Access to Traffic Server depends on Traffic Server
configuration options (such as access control lists).
T}
_
T{
\fB1\fP
T}	T{
Client certificates are \fBoptional\fP\&. If a client has a certificate,
then the certificate is validated. If the client does not have a
certificate, then the client is still allowed access to Traffic Server unless
access is denied through other Traffic Server configuration options.
T}
_
T{
\fB2\fP
T}	T{
Client certificates are \fBrequired\fP\&. The client must be authenticated
during the SSL handshake. Clients without a certificate are not
allowed to access Traffic Server\&.
T}
_
.TE
.INDENT 0.0
.TP
.B proxy.config.ssl.server.multicert.filename
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
ssl_multicert.config.UNINDENT
The location of the \fBssl_multicert.config\fP file, relative
to the Traffic Server configuration directory. In the following
example, if the Traffic Server configuration directory is
\fI/etc/trafficserver\fP, the Traffic Server SSL configuration file
and the corresponding certificates are located in
\fI/etc/trafficserver/ssl\fP:
.INDENT 0.0
.INDENT 3.5
.sp
.nf
.ft C
CONFIG proxy.config.ssl.server.multicert.filename STRING ssl/ssl_multicert.config
CONFIG proxy.config.ssl.server.cert.path STRING etc/trafficserver/ssl
CONFIG proxy.config.ssl.server.private_key.path STRING etc/trafficserver/ssl
.ft P
.fi
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.ssl.server.cert.path
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
/config.UNINDENT
The location of the SSL certificates and chains used for accepting
and validation new SSL sessions. If this is a relative path,
it is appended to the Traffic Server installation PREFIX. All
certificates and certificate chains listed in
\fBssl_multicert.config\fP will be loaded relative to this path.
.INDENT 0.0
.TP
.B proxy.config.ssl.server.private_key.path
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
NULL.UNINDENT
The location of the SSL certificate private keys. Change this
variable only if the private key is not located in the SSL
certificate file. All private keys listed in
\fBssl_multicert.config\fP will be loaded relative to this
path.
.INDENT 0.0
.TP
.B proxy.config.ssl.server.cert_chain.filename
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
NULL.UNINDENT
The name of a file containing a global certificate chain that
should be used with every server certificate. This file is only
used if there are certificates defined in \fBssl_multicert.config\fP\&.
Unless this is an absolute path, it is loaded relative to the
path specified by \fI\%proxy.config.ssl.server.cert.path\fP\&.
.INDENT 0.0
.TP
.B proxy.config.ssl.server.dhparams_file
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
NULL.UNINDENT
The name of a file containing a set of Diffie\-Hellman key exchange
parameters. If not specified, 2048\-bit DH parameters from \fI\%RFC 5114\fP are
used. These parameters are only used if a DHE (or EDH) cipher suite has
been selected.
.INDENT 0.0
.TP
.B proxy.config.ssl.CA.cert.path
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
NULL.UNINDENT
The location of the certificate authority file that client
certificates will be verified against.
.INDENT 0.0
.TP
.B proxy.config.ssl.CA.cert.filename
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
NULL.UNINDENT
The filename of the certificate authority that client certificates
will be verified against.
.INDENT 0.0
.TP
.B proxy.config.ssl.server.ticket_key.filename
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
ssl_ticket.key.UNINDENT
The filename of the default and global ticket key for SSL sessions. The location of the \fBssl_ticket.key\fP file, relative to the
\fI\%proxy.config.ssl.server.cert.path\fP directory.
.INDENT 0.0
.TP
.B proxy.config.ssl.max_record_size
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
This configuration specifies the maximum number of bytes to write
into a SSL record when replying over a SSL session. In some
circumstances this setting can improve response latency by reducing
buffering at the SSL layer. This setting can have a value between 0
and 16383 (max TLS record size).
.sp
The default of \fB0\fP means to always write all available data into
a single SSL record.
.sp
A value of \fB\-1\fP means TLS record size is dynamically determined. The
strategy employed is to use small TLS records that fit into a single
TCP segment for the first ~1 MB of data, but, increase the record size to
16 KB after that to optimize throughput. The record size is reset back to
a single segment after ~1 second of inactivity and the record size ramping
mechanism is repeated again.
.INDENT 0.0
.TP
.B proxy.config.ssl.session_cache
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
2.UNINDENT
Enables the SSL session cache:
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Description
T}
_
T{
\fB0\fP
T}	T{
Disables the session cache entirely.
T}
_
T{
\fB1\fP
T}	T{
Enables the session cache using OpenSSL\(aqs implementation.
T}
_
T{
\fB2\fP
T}	T{
Default. Enables the session cache using Traffic Server\(aqs implementation. This
implentation should perform much better than the OpenSSL
implementation.
T}
_
.TE
.INDENT 0.0
.TP
.B proxy.config.ssl.session_cache.timeout
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
This configuration specifies the lifetime of SSL session cache
entries in seconds. If it is \fB0\fP, then the SSL library will use
a default value, typically 300 seconds. Note: This option has no affect
when using the Traffic Server session cache (option \fB2\fP in
\fBproxy.config.ssl.session_cache\fP)
.INDENT 0.0
.INDENT 3.5
See \fIadmin\-performance\-timeouts\fP for more discussion on Traffic Server timeouts.
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.ssl.session_cache.auto_clear
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.UNINDENT
This will set the OpenSSL auto clear flag. Auto clear is enabled by
default with \fB1\fP it can be disabled by changing this setting to \fB0\fP\&.
.INDENT 0.0
.TP
.B proxy.config.ssl.session_cache.size
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
102400.UNINDENT
This configuration specifies the maximum number of entries
the SSL session cache may contain.
.INDENT 0.0
.TP
.B proxy.config.ssl.session_cache.num_buckets
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
256.UNINDENT
This configuration specifies the number of buckets to use with the
Traffic Server SSL session cache implementation. The TS implementation
is a fixed size hash map where each bucket is protected by a mutex.
.INDENT 0.0
.TP
.B proxy.config.ssl.session_cache.skip_cache_on_bucket_contention
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
This configuration specifies the behavior of the Traffic Server SSL session
cache implementation during lock contention on each bucket:
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Description
T}
_
T{
\fB0\fP
T}	T{
Default. Don\(aqt skip session caching when bucket lock is contented.
T}
_
T{
\fB1\fP
T}	T{
Disable the SSL session cache for a connection during lock contention.
T}
_
.TE
.INDENT 0.0
.TP
.B proxy.config.ssl.hsts_max_age
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
\-1.UNINDENT
This configuration specifies the max\-age value that will be used
when adding the Strict\-Transport\-Security header.  The value is in seconds.
A value of \fB0\fP will set the max\-age value to \fB0\fP and should remove the
HSTS entry from the client.  A value of \fB\-1\fP will disable this feature and
not set the header.  This option is only used for HTTPS requests and the
header will not be set on HTTP requests.
.INDENT 0.0
.TP
.B proxy.config.ssl.hsts_include_subdomains
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
Enables (\fB1\fP) or disables (\fB0\fP) adding the includeSubdomain value
to the Strict\-Transport\-Security header.  proxy.config.ssl.hsts_max_age
needs to be set to a non \fB\-1\fP value for this configuration to take effect.
.INDENT 0.0
.TP
.B proxy.config.ssl.allow_client_renegotiation
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
This configuration specifies whether the client is able to initiate
renegotiation of the SSL connection.  The default of \fB0\fP, means
the client can\(aqt initiate renegotiation.
.INDENT 0.0
.TP
.B proxy.config.ssl.cert.load_elevated
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
Enables (\fB1\fP) or disables (\fB0\fP) elevation of traffic_server
privileges during loading of SSL certificates.  By enabling this, SSL
certificate files\(aq access rights can be restricted to help reduce the
vulnerability of certificates.
.sp
This feature requires Traffic Server to be built with POSIX
capabilities enabled.
.INDENT 0.0
.TP
.B proxy.config.ssl.handshake_timeout_in
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
When enabled this limits the total duration for the server side SSL
handshake.
.sp
See \fIadmin\-performance\-timeouts\fP for more discussion on Traffic Server timeouts.
.INDENT 0.0
.TP
.B proxy.config.ssl.wire_trace_enabled
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
When enabled this turns on wire tracing of SSL connections that meet
the conditions specified by wire_trace_percentage, wire_trace_addr
and wire_trace_server_name.
.INDENT 0.0
.TP
.B proxy.config.ssl.wire_trace_percentage
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
This specifies the percentage of traffic meeting the other wire_trace
conditions to be traced.
.INDENT 0.0
.TP
.B proxy.config.ssl.wire_trace_addr
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
NULL.UNINDENT
This specifies the client IP for which wire_traces should be printed.
.INDENT 0.0
.TP
.B proxy.config.ssl.wire_trace_server_name
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
NULL.UNINDENT
This specifies the server name for which wire_traces should be
printed. This only works if traffic_server is built with
TS_USE_TLS_SNI flag set to true.
.SS Client\-Related Configuration
.INDENT 0.0
.TP
.B proxy.config.ssl.client.verify.server
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
Configures Traffic Server to verify the origin server certificate
with the Certificate Authority (CA).
.INDENT 0.0
.TP
.B proxy.config.ssl.client.cert.filename
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
NULL.UNINDENT
The filename of SSL client certificate installed on Traffic Server.
.INDENT 0.0
.TP
.B proxy.config.ssl.client.cert.path
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
/config.UNINDENT
The location of the SSL client certificate installed on Traffic
Server.
.INDENT 0.0
.TP
.B proxy.config.ssl.client.private_key.filename
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
NULL.UNINDENT
The filename of the Traffic Server private key. Change this variable
only if the private key is not located in the Traffic Server SSL
client certificate file.
.INDENT 0.0
.TP
.B proxy.config.ssl.client.private_key.path
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
NULL.UNINDENT
The location of the Traffic Server private key. Change this variable
only if the private key is not located in the SSL client certificate
file.
.INDENT 0.0
.TP
.B proxy.config.ssl.client.CA.cert.filename
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
NULL.UNINDENT
The filename of the certificate authority against which the origin
server will be verified.
.INDENT 0.0
.TP
.B proxy.config.ssl.client.CA.cert.path
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
NULL.UNINDENT
Specifies the location of the certificate authority file against
which the origin server will be verified.
.SH OCSP STAPLING CONFIGURATION
.INDENT 0.0
.TP
.B proxy.config.ssl.ocsp.enabled
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
Enable OCSP stapling.
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Description
T}
_
T{
\fB0\fP
T}	T{
Disables OCSP Stapling.
T}
_
T{
\fB1\fP
T}	T{
Allows Traffic Server to request SSL certificate revocation status from an OCSP
responder.
T}
_
.TE
.INDENT 0.0
.TP
.B proxy.config.ssl.ocsp.cache_timeout
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
3600.UNINDENT
Number of seconds before an OCSP response expires in the stapling cache.
.sp
See \fIadmin\-performance\-timeouts\fP for more discussion on Traffic Server timeouts.
.INDENT 0.0
.TP
.B proxy.config.ssl.ocsp.request_timeout
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
10.UNINDENT
Timeout (in seconds) for queries to OCSP responders.
.sp
See \fIadmin\-performance\-timeouts\fP for more discussion on Traffic Server timeouts.
.INDENT 0.0
.TP
.B proxy.config.ssl.ocsp.update_period
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
60.UNINDENT
Update period (in seconds) for stapling caches.
.SH HTTP/2 CONFIGURATION
.INDENT 0.0
.TP
.B proxy.config.http2.max_concurrent_streams_in
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
100.TP
.B Reloadable
Yes.UNINDENT
The maximum number of concurrent streams per inbound connection.
.sp
\fBNOTE:\fP
.INDENT 0.0
.INDENT 3.5
Reloading this value affects only new HTTP/2 connections, not the
ones already established.
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.http2.min_concurrent_streams_in
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
10.TP
.B Reloadable
Yes.UNINDENT
The minimum number of concurrent streams per inbound connection.
This is used when \fI\%proxy.config.http2.max_active_streams_in\fP is set
larger than \fB0\fP\&.
.INDENT 0.0
.TP
.B proxy.config.http2.max_active_streams_in
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.UNINDENT
Limits the maximum number of connection wide active streams.
When connection wide active streams are larger than this value,
SETTINGS_MAX_CONCURRENT_STREAMS will be reduced to
\fI\%proxy.config.http2.min_concurrent_streams_in\fP\&.
To disable, set to zero (\fB0\fP).
.INDENT 0.0
.TP
.B proxy.config.http2.initial_window_size_in
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1048576.TP
.B Reloadable
Yes.UNINDENT
The initial window size for inbound connections.
.INDENT 0.0
.TP
.B proxy.config.http2.max_frame_size
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
16384.TP
.B Reloadable
Yes.UNINDENT
Indicates the size of the largest frame payload that the sender is willing
to receive.
.INDENT 0.0
.TP
.B proxy.config.http2.header_table_size
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
4096.TP
.B Reloadable
Yes.UNINDENT
The maximum size of the header compression table used to decode header
blocks.
.INDENT 0.0
.TP
.B proxy.config.http2.max_header_list_size
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
4294967295.TP
.B Reloadable
Yes.UNINDENT
This advisory setting informs a peer of the maximum size of header list
that the sender is prepared to accept blocks. The default value, which is
the unsigned int maximum value in Traffic Server, implies unlimited size.
.INDENT 0.0
.TP
.B proxy.config.http2.stream_priority_enabled
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Reloadable
Yes.UNINDENT
Enable the experimental HTTP/2 Stream Priority feature.
.SH PLUG-IN CONFIGURATION
.INDENT 0.0
.TP
.B proxy.config.plugin.plugin_dir
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
config/plugins.UNINDENT
Specifies the location of Traffic Server plugins.
.INDENT 0.0
.TP
.B proxy.config.remap.num_remap_threads
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
When this variable is set to \fB0\fP, plugin remap callbacks are
executed in line on network threads. If remap processing takes
significant time, this can be cause additional request latency.
Setting this variable to causes remap processing to take place
on a dedicated thread pool, freeing the network threads to service
additional requests.
.SH SOCKS PROCESSOR
.INDENT 0.0
.TP
.B proxy.config.socks.socks_needed
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
Enables (\fB1\fP) or disables (\fB0\fP) the SOCKS processor
.INDENT 0.0
.TP
.B proxy.config.socks.socks_version
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
4.UNINDENT
Specifies the SOCKS version (\fB4\fP) or (\fB5\fP)
.INDENT 0.0
.TP
.B proxy.config.socks.socks_config_file
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
socks.config.UNINDENT
The socks_onfig file allows you to specify ranges of IP addresses
that will not be relayed to the SOCKS server. It can also be used
to configure AUTH information for SOCKSv5 servers.
.INDENT 0.0
.TP
.B proxy.config.socks.socks_timeout
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
100.UNINDENT
The activity timeout value (in seconds) for SOCKS server connections.
.sp
See \fIadmin\-performance\-timeouts\fP for more discussion on Traffic Server timeouts.
.INDENT 0.0
.TP
.B proxy.config.socks.server_connect_timeout
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
10.UNINDENT
The timeout value (in seconds) for SOCKS server connection attempts.
.sp
See \fIadmin\-performance\-timeouts\fP for more discussion on Traffic Server timeouts.
.INDENT 0.0
.TP
.B proxy.config.socks.per_server_connection_attempts
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.UNINDENT
The total number of connection attempts allowed per SOCKS server,
if multiple servers are used.
.INDENT 0.0
.TP
.B proxy.config.socks.connection_attempts
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
4.UNINDENT
The total number of connection attempts allowed to a SOCKS server
Traffic Server bypasses the server or fails the request
.INDENT 0.0
.TP
.B proxy.config.socks.server_retry_timeout
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
300.UNINDENT
The timeout value (in seconds) for SOCKS server connection retry attempts.
.sp
See \fIadmin\-performance\-timeouts\fP for more discussion on Traffic Server timeouts.
.INDENT 0.0
.TP
.B proxy.config.socks.default_servers
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
\fI*NONE*\fP.UNINDENT
Default list of SOCKS servers and their ports.
.INDENT 0.0
.TP
.B proxy.config.socks.server_retry_time
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
300.UNINDENT
The amount of time allowed between connection retries to a SOCKS
server that is unavailable.
.INDENT 0.0
.TP
.B proxy.config.socks.server_fail_threshold
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
2.UNINDENT
The number of times the connection to the SOCKS server can fail
before Traffic Server considers the server unavailable.
.INDENT 0.0
.TP
.B proxy.config.socks.accept_enabled
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
Enables (1) or disables (0) the SOCKS proxy option. As a SOCKS
proxy, Traffic Server receives SOCKS traffic (usually on port
1080) and forwards all requests directly to the SOCKS server.
.INDENT 0.0
.TP
.B proxy.config.socks.accept_port
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1080.UNINDENT
Specifies the port on which Traffic Server accepts SOCKS traffic.
.INDENT 0.0
.TP
.B proxy.config.socks.http_port
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
80.UNINDENT
Specifies the port on which Traffic Server accepts HTTP proxy requests
over SOCKS connections..
.SH SOCKETS
.INDENT 0.0
.TP
.B proxy.config.net.defer_accept
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.UNINDENT
default: \fB1\fP meaning \fBon\fP all Platforms except Linux: \fB45\fP seconds
.sp
This directive enables operating system specific optimizations for a listening socket. \fBdefer_accept\fP holds a call to \fBaccept(2)\fP
back until data has arrived. In Linux\(aq special case this is up to a maximum of 45 seconds.
.INDENT 0.0
.TP
.B proxy.config.net.listen_backlog
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
\-1
 :reloadable:.UNINDENT
This directive sets the maximum number of pending connections.
If it is set to \-1, Traffic Server will automatically set this
to a platform\-specific maximum.
.INDENT 0.0
.TP
.B proxy.config.net.tcp_congestion_control_in
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
"".UNINDENT
This directive will override the congestion control algorithm for incoming
connections (accept sockets). On linux the allowed values are typically
specified in a space separated list in /proc/sys/net/ipv4/tcp_allowed_congestion_control
.INDENT 0.0
.TP
.B proxy.config.net.tcp_congestion_control_out
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
STRING.TP
.B Default
"".UNINDENT
This directive will override the congestion control algorithm for outgoing
connections (connect sockets). On linux the allowed values are typically
specified in a space separated list in /proc/sys/net/ipv4/tcp_allowed_congestion_control
.INDENT 0.0
.TP
.B proxy.config.net.sock_send_buffer_size_in
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
Sets the send buffer size for connections from the client to Traffic Server.
.INDENT 0.0
.TP
.B proxy.config.net.sock_recv_buffer_size_in
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
Sets the receive buffer size for connections from the client to Traffic Server.
.INDENT 0.0
.TP
.B proxy.config.net.sock_option_flag_in
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0x5.UNINDENT
Turns different options "on" for the socket handling client connections::
.INDENT 0.0
.INDENT 3.5
.sp
.nf
.ft C
TCP_NODELAY  (1)
SO_KEEPALIVE (2)
SO_LINGER (4) \- with a timeout of 0 seconds
.ft P
.fi
.UNINDENT
.UNINDENT
.sp
\fBNOTE:\fP
.INDENT 0.0
.INDENT 3.5
This is a bitmask and you need to decide what bits to set.  Therefore,
you must set the value to \fB3\fP if you want to enable nodelay and
keepalive options above.
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.net.sock_send_buffer_size_out
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Overridable
Yes.UNINDENT
Sets the send buffer size for connections from Traffic Server to the origin server.
.INDENT 0.0
.TP
.B proxy.config.net.sock_recv_buffer_size_out
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.TP
.B Overridable
Yes.UNINDENT
Sets the receive buffer size for connections from Traffic Server to
the origin server.
.INDENT 0.0
.TP
.B proxy.config.net.sock_option_flag_out
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0x1.TP
.B Overridable
Yes.UNINDENT
Turns different options "on" for the origin server socket::
.INDENT 0.0
.INDENT 3.5
.sp
.nf
.ft C
TCP_NODELAY  (1)
SO_KEEPALIVE (2)
SO_LINGER (4) \- with a timeout of 0 seconds
.ft P
.fi
.UNINDENT
.UNINDENT
.sp
\fBNOTE:\fP
.INDENT 0.0
.INDENT 3.5
This is a bitmask and you need to decide what bits to set.  Therefore,
you must set the value to \fB3\fP if you want to enable nodelay and
keepalive options above.
.sp
When SO_LINGER is enabled, the linger timeout time is set
to 0. This is useful when Traffic Server and the origin server
are co\-located and large numbers of sockets are retained
in the TIME_WAIT state.
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.net.sock_mss_in
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
Same as the command line option \fB\-\-accept_mss\fP that sets the MSS for all incoming requests.
.INDENT 0.0
.TP
.B proxy.config.net.sock_packet_mark_in
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0x0.UNINDENT
Set the packet mark on traffic destined for the client
(the packets that make up a client response).
.sp
\fBSEE ALSO:\fP
.INDENT 0.0
.INDENT 3.5
\fI\%Traffic Shaping\fP
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.net.sock_packet_mark_out
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0x0.TP
.B Overridable
Yes.UNINDENT
Set the packet mark on traffic destined for the origin
(the packets that make up an origin request).
.sp
\fBSEE ALSO:\fP
.INDENT 0.0
.INDENT 3.5
\fI\%Traffic Shaping\fP
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.net.sock_packet_tos_in
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0x0.UNINDENT
Set the ToS/DiffServ Field on packets sent to the client
(the packets that make up a client response).
.sp
\fBSEE ALSO:\fP
.INDENT 0.0
.INDENT 3.5
\fI\%Traffic Shaping\fP
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.net.sock_packet_tos_out
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0x0.TP
.B Overridable
Yes.UNINDENT
Set the ToS/DiffServ Field on packets sent to the origin
(the packets that make up an origin request).
.sp
\fBSEE ALSO:\fP
.INDENT 0.0
.INDENT 3.5
\fI\%Traffic Shaping\fP
.UNINDENT
.UNINDENT
.INDENT 0.0
.TP
.B proxy.config.net.poll_timeout
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
10 (or 30 on Solaris).UNINDENT
Same as the command line option \fB\-\-poll_timeout\fP, or \fB\-t\fP, which
specifies the timeout used for the polling mechanism used. This timeout is
always in milliseconds (ms). This is the timeout to \fBepoll_wait()\fP on
Linux platforms, and to \fBkevent()\fP on BSD type OSs. The default value is
\fB10\fP on all platforms.
.sp
Changing this configuration can reduce CPU usage on an idle system, since
periodic tasks gets processed at these intervals. On busy servers, this
overhead is diminished, since polled events triggers morefrequently.
However, increasing the setting can also introduce additional latency for
certain operations, and timed events. It\(aqs recommended not to touch this
setting unless your CPU usage is unacceptable at idle workload. Some
alternatives to this could be:
.INDENT 0.0
.INDENT 3.5
.sp
.nf
.ft C
Reduce the number of worker threads (net\-threads)
Reduce the number of disk (AIO) threads
Make sure accept threads are enabled
.ft P
.fi
.UNINDENT
.UNINDENT
.sp
The relevant configurations for this are:
.INDENT 0.0
.INDENT 3.5
.sp
.nf
.ft C
CONFIG proxy.config.exec_thread.autoconfig INT 0
CONFIG proxy.config.exec_thread.limit INT 2
CONFIG proxy.config.accept_threads INT 1
CONFIG proxy.config.cache.threads_per_disk INT 8
.ft P
.fi
.UNINDENT
.UNINDENT
.sp
See \fIadmin\-performance\-timeouts\fP for more discussion on Traffic Server timeouts.
.INDENT 0.0
.TP
.B proxy.config.task_threads
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
2.UNINDENT
Specifies the number of task threads to run. These threads are used for
various tasks that should be off\-loaded from the normal network threads.
.INDENT 0.0
.TP
.B proxy.config.allocator.thread_freelist_size
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
512.UNINDENT
Sets the maximum number of elements that can be contained in a ProxyAllocator (per\-thread)
before returning the objects to the global pool
.INDENT 0.0
.TP
.B proxy.config.allocator.thread_freelist_low_watermark
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
32.UNINDENT
Sets the minimum number of items a ProxyAllocator (per\-thread) will guarantee to be
holding at any one time.
.INDENT 0.0
.TP
.B proxy.config.allocator.hugepages
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
Enable (1) the use of huge pages on supported platforms. (Currently only Linux)
.sp
You must also enable hugepages at the OS level. In a modern linux Kernel
this can be done by setting \fB/proc/sys/vm/nr_overcommit_hugepages\fP to a
sufficiently large value. It is reasonable to use (system
memory/hugepage size) because these pages are only created on demand.
.sp
For more information on the implications of enabling huge pages, see
\fIWikipedia <http://en.wikipedia.org/wiki/Page_%28computer_memory%29#Page_size_trade\-off>_\fP\&.
.INDENT 0.0
.TP
.B proxy.config.http.enabled
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
1.UNINDENT
Turn on or off support for HTTP proxying. This is rarely used, the one
exception being if you run Traffic Server with a protocol plugin, and would
like for it to not support HTTP requests at all.
.INDENT 0.0
.TP
.B proxy.config.http.wait_for_cache
.UNINDENT
.INDENT 0.0
.TP
.B Scope
CONFIG.TP
.B Type
INT.TP
.B Default
0.UNINDENT
Accepting inbound connections and starting the cache are independent
operations in Traffic Server\&. This variable controls the relative timing of these
operations and Traffic Server dependency on cache because if cache is required then
inbound connection accepts should be deferred until the validity of the
cache requirement is determined. Cache initialization failure will be logged
in \fBdiags.log\fP\&.
.TS
center;
|l|l|.
_
T{
Value
T}	T{
Description
T}
_
T{
\fB0\fP
T}	T{
Decouple inbound connections and cache initialization. Connections
will be accepted as soon as possible and Traffic Server will run regardless of
the results of cache initialization.
T}
_
T{
\fB1\fP
T}	T{
Do not accept inbound connections until cache initialization has
finished. Traffic Server will run regardless of the results of cache
initialization.
T}
_
T{
\fB2\fP
T}	T{
Do not accept inbound connections until cache initialization has
finished and been sufficiently successful that cache is enabled. This
means at least one cache span is usable. If there are no spans in
\fBstorage.config\fP or none of the spans can be successfully parsed
and initialized then Traffic Server will shut down.
T}
_
T{
\fB3\fP
T}	T{
Do not accept inbound connections until cache initialization has
finished and been completely successful. This requires at least one
cache span in \fBstorage.config\fP and that every span specified is
valid and successfully initialized. Any error will cause Traffic Server to shut
down.
T}
_
.TE
.SH COPYRIGHT
2015, dev@trafficserver.apache.org
.\" Generated by docutils manpage writer.
.