SYSTEMD-JOURNALD(8) systemd-journald SYSTEMD-JOURNALD(8)NAME
systemd-journald.service, systemd-journald - systemd Journal Service
SYNOPSISsystemd-journald.service
/usr/lib/systemd/systemd-journald
DESCRIPTION
systemd-journald is a system service that collects and stores logging
data. It creates and maintains structured, indexed journals based on
logging information that is received from the kernel, from user
processes via the libc syslog(3) call, from STDOUT/STDERR of system
services or via its native API. It will implicitly collect numerous
meta data fields for each log messages in a secure and unfakeable way.
See systemd.journal-fields(7) for more information about the collected
meta data.
Log data collected by the journal is primarily text based but can also
include binary data where necessary. All objects stored in the journal
can be up to 2^64-1 bytes in size.
By default the journal stores log data in /run/log/journal/. Since
/run/ is volatile log data is lost at reboot. To make the data
persistent it is sufficient to create /var/log/journal/ where
systemd-journald will then store the data.
systemd-journald will forward all received log messages to the AF_UNIX
SOCK_DGRAM socket /run/systemd/journal/syslog (if it exists) which may
be used by UNIX syslog daemons to process the data further.
See journald.conf(5) for information about the configuration of this
service.
SIGNALS
SIGUSR1
Request that journal data from /run/ is flushed to /var/ in order
to make it persistent (if this is enabled). This may be used after
/var/ is mounted, but is generally not required since the first
journal write when /var/ becomes writable triggers the flushing
anyway.
SIGUSR2
Request immediate rotation of the journal files.
SEE ALSOsystemd(1), journalctl(1), journald.conf(5), systemd.journal-fields(7)AUTHOR
Lennart Poettering <lennart@poettering.net>
Developer
systemd 02/15/2013 SYSTEMD-JOURNALD(8)
