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SYSLOGD(8) System Manager's Manual (smm) SYSLOGD(8)

NAME

syslogd
log systems messages

SYNOPSIS

syslogd [options ...]

DESCRIPTION

syslogd reads and logs messages to the system console, log files, other machines and/or users as specified by its configuration file.

OPTIONS

, --ipv4
Restrict to IPv4 transport (default).
, --ipv6
Restrict to IPv6 transport.
Allow transport with IPv4 and IPv6.
socket
Specify additional sockets from that syslogd has to listen to. This is needed if you are going to let some daemon run within a chroot()'ed environment. You can specify up to 19 additional sockets.
, --bind addr
Bind listener to this address/name.
, --bind-port port
Bind listener to this port.
, --rcfile file
Specify the pathname of an alternate configuration file; the default is system specific and displayed in the help output.
, --rcdir dir
Specify the pathname of an alternate configuration directory; the default is system specific and displayed in the help output.
, --hop
Enable forwarding remote messages. By default syslogd will not forward messages it receives from remote hosts.
host_list
A colon-seperated lists of hosts which should be considered local; they are logged by their hostnames instead by their FQDN.
domain_list
A colon-seperated list of domainnames which should be stripped from the FQDNs of hosts when logging.
, --mark interval
Select the number of minutes between ``mark'' messages; the default is 20 minutes. Setting it to 0 disables timestamps.
, --socket path
Specify the pathname of an alternate log socket. The default is system specific and displayed in the help output.
, --inet
Enable to receive remote messages using an internet domain socket. The default is to not receive any messages from the network. Older version always accepted remote messages.
, --local-time
Set local time on received messages.
, --sync
Force a file sync on every line.
, --no-detach
Suppress backgrounding and detachment of the daemon from its controlling terminal.
Do not listen to the kernel log device. This is only supported on systems which define a kernel log device, on all others this is already the default, and the option will be silently ignored.
Do not listen to any unix domain socket. This option overrides -p and -a.
Do not forward any messages. This overrides -h.
, --debug
Enter debug mode. syslogd does not put itself in the background, does not fork and shows debug information.
-?, --help
Display help information and exit.
Display a short usage message and exit.
, --version
Print version number and exit.

syslogd reads its configuration file when it starts up and whenever it receives a hangup signal. For information on the format of the configuration file, see syslog.conf(5).

syslogd reads messages from the UNIX domain socket /dev/log, from an Internet domain socket specified in /etc/services, and from the one of the special devices /dev/klog or /proc/kmsg depending on the system (to read kernel messages). In a GNU/Linux system it will not parse the System.map and use it to annotate the kernel messages.

syslogd creates the file /var/run/syslog.pid, and stores its process id there. This can be used to kill or reconfigure syslogd.

The message sent to syslogd should consist of a single line. The message can contain a priority code, which should be a preceding decimal number in angle braces, for example, ‘⟨5.⟩’ This priority code should map into the priorities defined in the include file ⟨sys/syslog.h⟩.

FILES

/etc/syslog.conf
The configuration file.
/var/run/syslog.pid
The process id of current syslogd.
/dev/log
Name of the UNIX domain datagram log socket.
/dev/klog, /proc/kmsg
The kernel log device.

SEE ALSO

logger(1), syslog(3), services(5), syslog.conf(5)

HISTORY

The syslogd command appeared in 4.3BSD.
February 9, 2019 GNU Network Utilities