Systemd Cheat Sheet

I'm still getting used to systemd commands and syntax. Here are some common tasks and their commands. (**This is a living doc and content will be added as needed)

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Show duration of the last boot:

$ systemd-analyze

Show how long each systemd unit took to start on last boot:

$ systemd-analyze blame

Show the systemd journal:

$ journalctl

Show all systemd journal events for today:

$ journalctl --since=today

Show all errors in the systemd journal:

$ journalctl -p err

Show the default run level:

$ systemctl get-default

Set default run level:

$ ln -sf /lib/systemd/system/<target name>.target /etc/systemd/system/default.target

Set default run level to multi-user (run level 3):

$ ln -sf /lib/systemd/system/multi-user.target /etc/systemd/system/default.target

Set default run level to graphical (run level 5):

$ ln -sf /lib/systemd/system/graphical.target /etc/systemd/system/default.target

Change to a different run level:

$ systemctl isolate <target name>.target

List active "units", as they are called (i.e. services, targets, mounts, etc):

$ systemctl

List units that are services:

$ systemctl -t service

List the status of a specific unit:

$ systemctl status <unit>

Example:

$ systemctl status sshd.service

Check if a service is enabled:

$ systemctl is-enabled <service>

Example:

$ systemctl is-enabled sshd.service
$ enabled

Kill all the processes of a given service:

$ systemctl kill <name>.service

Example:

$ systemctl kill crond.service

List all units and their state:

$ systemctl list-unit-files

Reload systemd, scanning for new or changed units:

$ systemctl daemon-reload

Display process details plus control group info. This is a great command to make an alias for.

$ ps xawf -eo pid,user,cgroup,args

Set the hostname:

$ hostnamectl set-hostname <name>