systemd

notes

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systemd.man.html

SIGUSR1
Request that journal data from /run/ is flushed to /var/ in order to make it persistent (if this is enabled). 
This must be used after /var/ is mounted, as otherwise log data from /run/ is never flushed to /var/ regardless of 
the configuration. 
Use the journalctl --flush command to request flushing of the journal files, and wait for the operation to complete. 
See journalctl(1) for details.

SIGUSR2
Request immediate rotation of the journal files. Use the journalctl --rotate command to request journal file rotation, and 
wait for the operation to complete.

SIGRTMIN+1
Request that all unwritten log data is written to disk. Use the journalctl --sync command to trigger journal synchronization, and 
wait for the operation to complete.

systemd.directives.html

systemd.generators: postfix-instance sysv, system-update, rc-local, hibernate-resume, gpt-auto, getty, fstab, debug, cryptsetup