systemctl
works with not only services but all other unit types, and is a valuable tool when monitoring or troubleshooting a system. It can list all known units, limit the results to a single unit type, show only failed units, or examine unit relationships. The table below shows some useful systemctl
features and should help system administrators replace their old workflow in sysVinit.
systemctl
command reference
sysVinit command | systemd command | Notes |
service sshd start | systemctl start sshd.service | Used to start a service (not reboot persistent) |
service sshd stop | systemctl stop sshd.service | Used to stop a service. (not reboot persistent) |
service sshd restart | systemctl restart sshd.service | Used to start and stop a service. |
service sshd reload | systemctl reload sshd.service | When supported, reloads the config file without interrupting pending operations. |
service sshd condrestart | systemctl condrestart sshd.service | Restarts if the service is already running. |
service sshd status | systemctl status sshd.service | Tells whether a service is currently running. |
ls /etc/rc.d/init.d/ | systemctl list-unit-files --type=service | Lists all available services. |
chkconfig sshd on | systemctl enable sshd.service | Always run the service at this target (runlevel.) |
chkconfig sshd off | systemctl disable sshd.service | Do not automatically run the service at this target (runlevel.) |
chkconfig --list | systemctl list-units -t service --all | Print a table of available services and their status. |
chkconfig sshd --list | ls /etc/systemd/system/*.wants/sshd.service | Lists the targets that will include the service. |
chkconfig sshd --add | systemctl daemon-reload | Used when you create a service file or modify any configuration. |
telinit 3 | systemctl isolate multi-user.target | Move system into another target (change runlevels.) |
[no comparable command] | systemctl show -p "Wants" multi-user.target | Lists units pulled in by a given target. |
[no comparable command] | systemctl show -p "After" sshd.service | Shows dependent services and other targets. |
[no comparable command] | systemd --test --system --unit=multi-user.target | Simulates booting the system to a given target |
[no comparable command] | systemd-analyze plot > boot.svg | Generates a diagnostically useful graphical representation of the boot process. |
ps xawf -eo pid,user,cgroup,args | systemd-cgls | Display control group process tree. |
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