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.\" ========================================================================
.\"
.IX Title "gmond.conf 5"
.TH gmond.conf 5 "2015-07-01" "ganglia/3.7.2" "Ganglia Monitoring System"
.\" For nroff, turn off justification. Always turn off hyphenation; it makes
.\" way too many mistakes in technical documents.
.if n .ad l
.nh
.SH "NAME"
gmond.conf \- configuration file for ganglia monitoring
daemon (gmond)
.SH "DESCRIPTION"
.IX Header "DESCRIPTION"
The gmond.conf file is used to configure the ganglia
monitoring daemon (gmond) which is part of the \fBGanglia
Distributed Monitoring System\fR.
.SH "SECTIONS AND ATTRIBUTES"
.IX Header "SECTIONS AND ATTRIBUTES"
All sections and attributes are case-insensitive. For example,
\&\fBname\fR or \fB\s-1NAME\s0\fR or \fBName\fR or \fBNaMe\fR are all equivalent.
.PP
Some sections can be included in the configuration file multiple
times and some sections are singular. For example, you can
have only one \fBcluster\fR section to define the attributes of
the cluster being monitored; however, you can have multiple
\&\fBudp_recv_channel\fR sections to allow gmond to receive message
on multiple \s-1UDP\s0 channels.
.SS "cluster"
.IX Subsection "cluster"
There should only be one \fBcluster\fR section defined. This
section controls how gmond reports the attributes of the
cluster that it is part of.
.PP
The \fBcluster\fR section has four attributes: \fBname\fR,
\&\fBowner\fR, \fBlatlong\fR and \fBurl\fR.
.PP
For example,
.PP
.Vb 6
\& cluster {
\& name = "Millennium Cluster"
\& owner = "UC Berkeley CS Dept."
\& latlong = "N37.37 W122.23"
\& url = "http://www.millennium.berkeley.edu/"
\& }
.Ve
.PP
The \fBname\fR attributes specifies the name of the cluster of
machines. The \fBowner\fR tag specifies the administrators of
the cluster. The pair \fBname\fR/\fBowner\fR should be unique
to all clusters in the world.
.PP
The \fBlatlong\fR attribute is the latitude and longitude \s-1GPS\s0
coordinates of this cluster on earth. Specified to 1 mile
accuracy with two decimal places per axis in decimal.
.PP
The \fBurl\fR for more information on the \fBcluster\fR.
Intended to give purpose, owner, administration, and account details
for this cluster.
.PP
There directives directly control the \s-1XML\s0 output of gmond. For
example, the cluster configuration example above would translate
into the following \s-1XML\s0.
.PP
.Vb 4
\&
\& ...
\&
.Ve
.SS "host"
.IX Subsection "host"
The \fBhost\fR section provides information about the host running this
instance of \fBgmond\fR. Currently only the \fBlocation\fR string attribute is
supported. Example:
.PP
.Vb 3
\& host {
\& location = "1,2,3"
\& }
.Ve
.PP
The numbers represent Rack, Rank and Plane respectively.
.SS "globals"
.IX Subsection "globals"
The \fBglobals\fR section controls general characteristics of gmond
such as whether is should daemonize, what user it should run as,
whether is should send/receive date and such. The \fBglobals\fR
section has the following attributes: \fBdaemonize\fR, \fBsetuid\fR, \fBuser\fR,
\&\fBdebug_level\fR, \fBmute\fR, \fBdeaf\fR, \fBallow_extra_data\fR, \fBhost_dmax\fR,
\&\fBhost_tmax\fR, \fBcleanup_threshold\fR, \fBgexec\fR, \fBsend_metadata_interval\fR
and \fBmodule_dir\fR.
.PP
For example,
.PP
.Vb 7
\& globals {
\& daemonize = true
\& setuid = true
\& user = nobody
\& host_dmax = 3600
\& host_tmax = 40
\& }
.Ve
.PP
The \fBdaemonize\fR attribute is a boolean. When true, \fBgmond\fR will
daemonize. When false, \fBgmond\fR will run in the foreground.
.PP
The \fBsetuid\fR attribute is a boolean. When true, \fBgmond\fR will
set its effective \s-1UID\s0 to the uid of the user specified by the \fBuser\fR
attribute. When false, \fBgmond\fR will not change its effective user.
.PP
The \fBdebug_level\fR is an integer value. When set to zero (0), \fBgmond\fR
will run normally. A \fBdebug_level\fR greater than zero will result in
\&\fBgmond\fR running in the foreground and outputting debugging information.
The higher the \fBdebug_level\fR the more verbose the output.
.PP
The \fBmute\fR attribute is a boolean. When true, \fBgmond\fR will not
send data regardless of any other configuration directives.
.PP
The \fBdeaf\fR attribute is a boolean. When true, \fBgmond\fR will not
receive data regardless of any other configuration directives.
.PP
The \fBallow_extra_data\fR attribute is a boolean. When false, \fBgmond\fR will
not send out the \s-1EXTRA_ELEMENT\s0 and \s-1EXTRA_DATA\s0 parts of the \s-1XML\s0. This might
be useful if you are using your own frontend to the metric data and will
like to save some bandwidth.
.PP
The \fBhost_dmax\fR value is an integer with units in seconds. When set
to zero (0), \fBgmond\fR will never delete a host from its list even when
a remote host has stopped reporting. If \fBhost_dmax\fR is set to a
positive number then \fBgmond\fR will flush a host after it has not heard
from it for \fBhost_dmax\fR seconds. By the way, dmax means \*(L"delete max\*(R".
.PP
The \fBhost_tmax\fR value is an integer with units in seconds. This value
represents the maximum amount of time that \fBgmond\fR should wait between
updates from a host. As messages may get lost in the network, \fBgmond\fR
will consider the host as being down if it has not received any messages
from it after 4 times this value. For example, if \fBhost_tmax\fR is set
to 20, the host will appear as down after 80 seconds with no messages
from it. By the way, tmax means \*(L"timeout max\*(R".
.PP
The \fBcleanup_threshold\fR is the minimum amount of time before gmond
will cleanup any hosts or metrics where \fBtn\fR > \fBdmax\fR a.k.a. expired
data.
.PP
The \fBgexec\fR boolean allows you to specify whether gmond will announce
the hosts availability to run gexec jobs. \fBNote\fR: this requires
that \fBgexecd\fR is running on the host and the proper keys have been
installed.
.PP
The \fBsend_metadata_interval\fR establishes an interval in which gmond
will send or resend the metadata packets that describe each enabled
metric. This directive by default is set to 0 which means that gmond will
only send the metadata packets at startup and upon request from other
gmond nodes running remotely. If a new machine running gmond is added
to a cluster, it needs to announce itself and inform all other nodes of the
metrics that it currently supports. In multicast mode, this isn't a problem
because any node can request the metadata of all other nodes in the cluster.
However in unicast mode, a resend interval must be established. The interval
value is the minimum number of seconds between resends.
.PP
The \fBoverride_hostname\fR and \fBoverride_ip\fR parameters allow an arbitrary
hostname and/or \s-1IP\s0 (hostname can be optionally specified without \s-1IP\s0) to
use when identifying metrics coming from this host.
.PP
The \fBmodule_dir\fR is an optional parameter indicating the directory where
the \s-1DSO\s0 modules are to be located. If absent, the value to use is set at
configure time with the \-\-with\-moduledir option which will default if omitted
to the a subdirectory named \*(L"ganglia\*(R" in the directory where libganglia will
be installed.
.PP
For example, in a 32\-bit Intel compatible Linux host that is usually:
.PP
.Vb 1
\& /usr/lib/ganglia
.Ve
.SS "udp_send_channel"
.IX Subsection "udp_send_channel"
You can define as many \fBudp_send_channel\fR sections as you like within
the limitations of memory and file descriptors. If \fBgmond\fR is configured
as \fBmute\fR this section will be ignored.
.PP
The \fBudp_send_channel\fR has a total of seven attributes: \fBmcast_join\fR,
\&\fBmcast_if\fR, \fBhost\fR, \fBport\fR, \fBttl\fR, \fBbind\fR and \fBbind_hostname\fR.
\&\fBbind\fR and \fBbind_hostname\fR are mutually exclusive.
.PP
For example, the 2.5.x version gmond would send on the following single channel
by default...
.PP
.Vb 4
\& udp_send_channel {
\& mcast_join = 239.2.11.71
\& port = 8649
\& }
.Ve
.PP
The \fBmcast_join\fR and \fBmcast_if\fR attributes are optional. When specified
\&\fBgmond\fR will create the \s-1UDP\s0 socket and join the \fBmcast_join\fR multicast group
and send data out the interface specified by \fBmcast_if\fR.
.PP
You can use the \fBbind\fR attribute to bind to a particular local address to
be used as the source for the multicast packets sent or let gmond resolve the
default hostname if \fBbind_hostname\fR = yes.
.PP
If only a \fBhost\fR and \fBport\fR are specified then \fBgmond\fR will send unicast \s-1UDP\s0
messages to the hosts specified.
.PP
You could specify multiple unicast hosts for redundancy as \fBgmond\fR will send
\&\s-1UDP\s0 messages to all \s-1UDP\s0 channels.
.PP
Be careful though not to mix multicast and unicast attributes in the same
udp_send_channel definition.
.PP
For example...
.PP
.Vb 8
\& udp_send_channel {
\& host = host.foo.com
\& port = 2389
\& }
\& udp_send_channel {
\& host = 192.168.3.4
\& port = 2344
\& }
.Ve
.PP
would configure gmond to send messages to two hosts. The \fBhost\fR specification
can be an IPv4/IPv6 address or a resolvable hostname.
.PP
The \fBttl\fR attribute lets you modify the Time-To-Live (\s-1TTL\s0) of outgoing messages
(unicast or multicast).
.SS "udp_recv_channel"
.IX Subsection "udp_recv_channel"
You can specify as many \fBudp_recv_channel\fR sections as you like within the
limits of memory and file descriptors. If \fBgmond\fR is configured \fBdeaf\fR
this attribute will be ignored.
.PP
The \fBudp_recv_channel\fR section has following attributes:
\&\fBmcast_join\fR, \fBbind\fR, \fBport\fR, \fBmcast_if\fR, \fBfamily\fR, \fBretry_bind\fR
and \fBbuffer\fR.
The \fBudp_recv_channel\fR can also have an \fBacl\fR definition (see
\&\s-1ACCESS\s0 \s-1CONTROL\s0 \s-1LISTS\s0 below).
.PP
For example, the 2.5.x gmond ran with a single udp receive channel...
.PP
.Vb 5
\& udp_recv_channel {
\& mcast_join = 239.2.11.71
\& bind = 239.2.11.71
\& port = 8649
\& }
.Ve
.PP
The \fBmcast_join\fR and \fBmcast_if\fR should only be used if you want to
have this \s-1UDP\s0 channel receive multicast packets the multicast
group \fBmcast_join\fR on interface \fBmcast_if\fR. If you do not specify
multicast attributes then \fBgmond\fR will simply create a \s-1UDP\s0 server
on the specified \fBport\fR.
.PP
You can use the \fBbind\fR attribute to bind to a particular local address.
.PP
The family address is set to \fBinet4\fR by default. If you want to bind
the port to an \fBinet6\fR port, you need to specify that in the family
attribute. Ganglia will not allow IPV6=>\s-1IPV4\s0 mapping (for portability
and security reasons). If you want to listen on both \fBinet4\fR and
\&\fBinet6\fR for a particular port, explicitly state it with the following:
.PP
.Vb 8
\& udp_recv_channel {
\& port = 8666
\& family = inet4
\& }
\& udp_recv_channel {
\& port = 8666
\& family = inet6
\& }
.Ve
.PP
If you specify a bind address, the family of that address takes precedence.
f your IPv6 stack doesn't support \s-1IPV6_V6ONLY\s0, a warning will be issued
but gmond will continue working (this should rarely happen).
.PP
Multicast Note: for multicast, specifying a \fBbind\fR address with the same
value used for \fBmcast_join\fR will prevent unicast \s-1UDP\s0 messages to the same
\&\fBport\fR from being processed.
.PP
The sFlow protocol (see http://www.sflow.org) can be used to collect
a standard set of performance metrics from servers. For servers that
don't include embedded sFlow agents, an open source sFlow agent is available
on SourceForge (see http://host\-sflow.sourceforge.net).
.PP
To configure \fBgmond\fR to receive sFlow datagrams, simply
add a \fBudp_recv_channel\fR with the \fBport\fR set to 6343 (the \s-1IANA\s0 registered
port for sFlow):
.PP
.Vb 3
\& udp_recv_channel {
\& port = 6343
\& }
.Ve
.PP
Note: sFlow is unicast protocol, so don't include \fBmcast_join\fR join.
Note: To use some other port for sFlow, set it here and then specify the port
in an \fBsflow\fR section (see below).
.PP
\&\fBgmond\fR will fail to run if it can't bind to all defined
\&\fBudp_recv_channel\fRs. Sometimes, on machines configured by \s-1DHCP\s0,
for example, the \fBgmond\fR daemon starts before a network address is
assigned to the interface. Consequently, the bind fails and the
\&\fBgmond\fR daemon does not run. To assist in this situation, the
boolean parameter \fBretry_bind\fR can be set to the value \fBtrue\fR
and then the daemon will not abort on failure, it will enter a
loop and repeat the bind attempt every 60 seconds:
.PP
.Vb 4
\& udp_recv_channel {
\& port = 6343
\& retry_bind = true
\& }
.Ve
.PP
If you have a large system with lots of metrics, you might experience
\&\s-1UDP\s0 drops. This happens when \fBgmond\fR is not able to process the \s-1UDP\s0
fast enough from the network. In this case you might consider changing
your setup into a more distributed setup using aggregator \fBgmond\fR hosts.
Alternatively you can choose to create a bigger receive \fBbuffer\fR:
.PP
.Vb 6
\& udp_recv_channel {
\& port = 6343
\& buffer = 10485760
\& }
\&B is specified in bytes, i.e.: 10485760 will allow 10MB UDP
\&to be buffered in memory.
.Ve
.PP
Note: increasing buffer size will increase memory usage by \fBgmond\fR
.SS "tcp_accept_channel"
.IX Subsection "tcp_accept_channel"
You can specify as many \fBtcp_accept_channel\fR sections as you like
within the limitations of memory and file descriptors. If \fBgmond\fR
is configured to be \fBmute\fR, then these sections are ignored.
.PP
The \fBtcp_accept_channel\fR has the following attributes: \fBbind\fR, \fBport\fR,
\&\fBinterface\fR, \fBfamily\fR and \fBtimeout\fR. A \fBtcp_accept_channel\fR may also have
an \fBacl\fR section specified (see \s-1ACCESS\s0 \s-1CONTROL\s0 \s-1LISTS\s0 below).
.PP
For example, 2.5.x gmond would accept connections on a single \s-1TCP\s0
channel.
.PP
.Vb 3
\& tcp_accept_channel {
\& port = 8649
\& }
.Ve
.PP
The \fBbind\fR address is optional and allows you to specify which
local address \fBgmond\fR will bind to for this channel.
.PP
The \fBport\fR is an integer than specifies which port to answer
requests for data.
.PP
The \fBfamily\fR address is set to \fBinet4\fR by default. If you want to bind
the port to an \fBinet6\fR port, you need to specify that in the family
attribute. Ganglia will not allow IPV6=>\s-1IPV4\s0 mapping (for portability
and security reasons). If you want to listen on both \fBinet4\fR and
\&\fBinet6\fR for a particular port, explicitly state it with the following:
.PP
.Vb 8
\& tcp_accept_channel {
\& port = 8666
\& family = inet4
\& }
\& tcp_accept_channel {
\& port = 8666
\& family = inet6
\& }
.Ve
.PP
If you specify a bind address, the family of that address takes precedence.
If your IPv6 stack doesn't support \s-1IPV6_V6ONLY\s0, a warning will be issued
but gmond will continue working (this should rarely happen).
.PP
The \fBtimeout\fR attribute allows you to specify how many microseconds to block
before closing a connection to a client. The default is set to \-1 (blocking
\&\s-1IO\s0) and will never abort a connection regardless of how slow the client is
in fetching the report data.
.PP
The \fBinterface\fR is not implemented at this time (use \fBbind\fR).
.SS "collection_group"
.IX Subsection "collection_group"
You can specify as many \fBcollection_group\fR section as you like
within the limitations of memory. A \fBcollection_group\fR has
the following attributes: \fBcollect_once\fR, \fBcollect_every\fR
and \fBtime_threshold\fR. A \fBcollection_group\fR must also contain one
or more \fBmetric\fR sections.
.PP
The \fBmetric\fR section has the following attributes: (one of \fBname\fR
or \fBname_match\fR; \fBname_match\fR is only permitted if pcre support is
compiled in), \fBvalue_threshold\fR and \fBtitle\fR. For a list of
available metric names, run the following command:
.PP
.Vb 1
\& % gmond \-m
.Ve
.PP
Here is an example of a collection group for a static metric...
.PP
.Vb 8
\& collection_group {
\& collect_once = yes
\& time_threshold = 1800
\& metric {
\& name = "cpu_num"
\& title = "Number of CPUs"
\& }
\& }
.Ve
.PP
This \fBcollection_group\fR entry would cause gmond to collect the
\&\fBcpu_num\fR metric once at startup (since the number of CPUs will not
change between reboots). The metric \fBcpu_num\fR would be send
every 1/2 hour (1800 seconds). The default value for the \fBtime_threshold\fR
is 3600 seconds if no \fBtime_threshold\fR is specified.
.PP
The \fBtime_threshold\fR is the maximum amount of time that can pass before
gmond sends all \fBmetric\fRs specified in the \fBcollection_group\fR to all
configured \fBudp_send_channel\fRs. A \fBmetric\fR may be sent before this
\&\fBtime_threshold\fR is met if during collection the value surpasses the
\&\fBvalue_threshold\fR (explained below).
.PP
Here is an example of a collection group for a volatile metric...
.PP
.Vb 10
\& collection_group {
\& collect_every = 60
\& time_threshold = 300
\& metric {
\& name = "cpu_user"
\& value_threshold = 5.0
\& title = "CPU User"
\& }
\& metric {
\& name = "cpu_idle"
\& value_threshold = 10.0
\& title = "CPU Idle"
\& }
\& }
.Ve
.PP
This collection group would collect the \fBcpu_user\fR and \fBcpu_idle\fR metrics
every 60 seconds (specified in \fBcollect_every\fR). If \fBcpu_user\fR varies by
5.0% or \fBcpu_idle\fR varies by 10.0%, then the entire \fBcollection_group\fR
is sent. If no \fBvalue_threshold\fR is triggered within \fBtime_threshold\fR
seconds (in this case 300), the entire \fBcollection_group\fR is sent.
.PP
Each time the metric value is collected the new value is compared with
the old value collected. If the difference between the last value and
the current value is greater than the \fBvalue_threshold\fR, the entire
collection group is send to the \fBudp_send_channel\fRs defined.
.PP
It's important to note that all metrics in a collection group are sent
even when only a single \fBvalue_threshold\fR is surpassed.
.PP
In addition a user friendly title can be substituted for the metric name
by including a \fBtitle\fR within the \fBmetric\fR section.
.PP
By using the \fBname_match\fR parameter instead of \fBname\fR, it is possible
to use a single definition to configure multiple metrics that match a
regular expression. The perl compatible regular expression (pcre) syntax
is used. This approach is particularly useful for a series of metrics
that may vary in number between reboots (e.g. metric names that
are generated for each individual \s-1NIC\s0 or \s-1CPU\s0 core).
.PP
Here is an example of using the \fBname_match\fR directive to enable
the multicpu metrics:
.PP
.Vb 5
\& metric {
\& name_match = "multicpu_([a\-z]+)([0\-9]+)"
\& value_threshold = 1.0
\& title = "CPU\-\e\e2 \e\e1"
\& }
.Ve
.PP
Note that in the example above, there are two matches: the alphabetical
match matches the variations of the metric name (e.g. \fBidle\fR, \fBsystem\fR)
while the numeric match matches the \s-1CPU\s0 core number. The second thing
to note is the use of substitutions within the argument to \fBtitle\fR.
.PP
If both \fBname\fR and \fBname_match\fR are specified, then \fBname\fR is ignored.
.SS "Modules"
.IX Subsection "Modules"
A \fBmodules\fR section contains the parameters that are necessary to load a
metric module. A metric module is a dynamically loadable module that
extends the available metrics that gmond is able to collect. Each \fBmodules\fR
section contains at least one \fBmodule\fR section. Within a \fBmodule\fR section
are the directives \fBname\fR, \fBlanguage\fR, \fBenabled\fR, \fBpath\fR and \fBparams\fR.
The module \fBname\fR is the name of the module as determined by the module
structure if the module was developed in C/\*(C+. Alternatively, the
\&\fBname\fR can be the name of the source file if the module has been
implemented in a interpreted language such as python. A \fBlanguage\fR
designation must be specified as a string value for each module. The
\&\fBlanguage\fR directive must correspond to the source code language in
which the module was implemented (ex. language = \*(L"python\*(R"). If a
\&\fBlanguage\fR directive does not exist for the module, the assumed
language will be \*(L"C/\*(C+\*(R". The \fBenabled\fR directive allows a metric module
to be easily enabled or disabled through the configuration file. If the
\&\fBenabled\fR directive is not included in the module configuration, the
enabled state will default to \*(L"yes\*(R". One thing to note is that if a
module has been disabled yet the metric which that module implements
is still listed as part of a collection group, gmond will produce a
warning message. However gmond will continue to function normally
by simply ignoring the metric. The \fBpath\fR is the path from which
gmond is expected to load the module (C/\*(C+ compiled dynamically
loadable module only). The \fBparams\fR directive can be used to pass
a single string parameter directly to the module initialization
function (C/\*(C+ module only). Multiple parameters can be passed to
the module's initialization function by including one or more
\&\fBparam\fR sections. Each \fBparam\fR section must be named and contain
a \fBvalue\fR directive. Once a module has been loaded, the additional
metrics can be discovered by invoking \fBgmond \-m\fR.
.PP
.Vb 10
\& modules {
\& module {
\& name = "example_module"
\& language = "C/C++"
\& enabled = yes
\& path = "modexample.so"
\& params = "An extra raw parameter"
\& param RandomMax {
\& value = 75
\& }
\& param ConstantValue {
\& value = 25
\& }
\& }
\& }
.Ve
.SS "sFlow"
.IX Subsection "sFlow"
The \fBsflow\fR group is optional and has the following optional
attributes: \fBudp_port\fR, \fBaccept_vm_metrics\fR, \fBaccept_http_metrics\fR,
\&\fBaccept_memcache_metrics\fR, \fBaccept_jvm_metrics\fR,
\&\fBmultiple_http_instances\fR,\fBmultiple_memcache_instances\fR,
\&\fBmultiple_jvm_instances\fR. By default, a
\&\fBudp_recv_channel\fR on port 6343 (the \s-1IANA\s0 registered port for
sFlow) is all that is required to accept and process sFlow
datagrams. To receive sFlow on some other port requires both
a \fBudp_recv_channel\fR for the other port and a \fBudp_port\fR
setting here. For example:
.PP
.Vb 3
\& udp_recv_channel {
\& port = 7343
\& }
\&
\& sflow {
\& udp_port = 7343
\& }
.Ve
.PP
An sFlow agent running on a hypervisor may also be sending
metrics for its local virtual machines. By default these
metrics are ignored, but the \fBaccept_vm_metrics\fR flag can
be used to accept those metrics too, and prefix them with
an identifier for each virtual machine.
.PP
.Vb 3
\& sflow {
\& accept_vm_metrics = yes
\& }
.Ve
.PP
The sFlow feed may also contain metrics sent from \s-1HTTP\s0 or memcached
servers, or from Java VMs. Extra options can be used to ignore
or accept these metrics, and to indicate that there may be multiple
instances per host. For example:
.PP
.Vb 4
\& sflow {
\& accept_http_metrics = yes
\& multiple_http_instances = yes
\& }
.Ve
.PP
will allow the \s-1HTTP\s0 metrics, and also mark them with a distinguishing
identifier so that each instance can be trended separately. (If multiple
instances are reporting and this flag is not set, the results are likely
to be garbled.)
.SS "Include"
.IX Subsection "Include"
This directive allows the user to include additional configuration files
rather than having to add all gmond configuration directives to the
gmond.conf file. The following example includes any file with the extension
of .conf contained in the directory conf.d as if the contents of the included
configuration files were part of the original gmond.conf file. This allows
the user to modularize their configuration file. One usage example might
be to load individual metric modules by including module specific .conf files.
.PP
include ('/etc/ganglia/conf.d/*.conf')
.SH "ACCESS CONTROL"
.IX Header "ACCESS CONTROL"
The \fBudp_recv_channel\fR and \fBtcp_accept_channel\fR directives
can contain an Access Control List (\s-1ACL\s0). This \s-1ACL\s0 allows you to specify
exactly which hosts gmond process data from.
.PP
An example of an \fBacl\fR entry looks like
.PP
.Vb 8
\& acl {
\& default = "deny"
\& access {
\& ip = 192.168.0.4
\& mask = 32
\& action = "allow"
\& }
\& }
.Ve
.PP
This \s-1ACL\s0 will by default reject all traffic that is not specifically from
host 192.168.0.4 (the mask size for an IPv4 address is 32, the mask size
for an IPv6 address is 128 to represent a single host).
.PP
Here is another example
.PP
.Vb 10
\& acl {
\& default = "allow"
\& access {
\& ip = 192.168.0.0
\& mask = 24
\& action = "deny"
\& }
\& access {
\& ip = ::ff:1.2.3.0
\& mask = 120
\& action = "deny"
\& }
\& }
.Ve
.PP
This \s-1ACL\s0 will by default allow all traffic unless it comes from the
two subnets specified with action = \*(L"deny\*(R".
.SH "EXAMPLE"
.IX Header "EXAMPLE"
The default behavior for a 2.5.x gmond would be specified as...
.PP
.Vb 12
\& udp_recv_channel {
\& mcast_join = 239.2.11.71
\& bind = 239.2.11.71
\& port = 8649
\& }
\& udp_send_channel {
\& mcast_join = 239.2.11.71
\& port = 8649
\& }
\& tcp_accept_channel {
\& port = 8649
\& }
.Ve
.PP
To see the complete default configuration for gmond simply run:
.PP
.Vb 1
\& % gmond \-t
.Ve
.PP
gmond will print out its default behavior in a configuration file
and then exit. Capturing this output to a file can serve as
a useful starting point for creating your own custom configuration.
.PP
.Vb 1
\& % gmond \-t > custom.conf
.Ve
.PP
edit \fBcustom.conf\fR to taste and then
.PP
.Vb 1
\& % gmond \-c ./custom.conf
.Ve
.SH "SEE ALSO"
.IX Header "SEE ALSO"
\&\fIgmond\fR\|(1).
.SH "NOTES"
.IX Header "NOTES"
The ganglia web site is at http://ganglia.info/.
.SH "COPYRIGHT"
.IX Header "COPYRIGHT"
Copyright (c) 2005 The University of California, Berkeley