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Systemd Cheatsheet

Basic Commands

Good news - tab complete works here! new

• start and stop service - reload - reloads config only - not all services have this option

$ systemctl {start | stop | restart | reload} daemon.service

• List services (this is dumb - too long to type - probably want to alias this in .bashrc -- or get the bugs out of bash-complete (they did))

$ systemctl list-unit-files --type=service  

• Enable service (default run levels)

$ systemctl {enable | disable} daemon.service 

• get status

$ systemctl status daemon.service

• Reboot and powerdown

$ systemctl { poweroff | reboot }

Advanced

• Show properties of one or more units - most often you would use status instead

$ systemctl show daemon.service 

• List or cancel jobs - good to stop a hung bug

$ systemctl {list | cancel}-jobs

Debug commands

• Get a good idea if everything started right or not - think of a log of systemd

$ journalctl -alb

• Find what is slowing boot up

$ systemd-analyze 
Startup finished in 2.974s (kernel) + 18.109s (userspace) = 21.084s

$ systemd-analyze blame 

• prints a list of all running units, ordered by the time they took to initialize.

$ systemd-analyze plot

• prints an SVG graphic detailing which system services have been started at what time, highlighting the time they spent on initialization.

$ systemd-analyze plot 

• may be used to determine system boot-up performance statistics and retrieve other state and tracing information from the system and service manager.

$ systemd-analyze 

• prints the time spent in the kernel before userspace has been reached, the time spent in the initial RAM disk (initrd) before normal system userspace has been reached, and the time normal system userspace took to initialize.

Systemd services

• systemd-timesyncd.service

Edit /etc/systemd/timesyncd.conf if you want to point at your own time server - the keyword Servers needs a Capital 's' and the s at the end.

This service synchronizes the local system clock with a Network Time Protocol Server(s). If you want to run your own time server install ntp.