# Troubleshooting Services With 'systemctl` To view a description of all the active, loaded units, execute the systemctl command without any options or arguments: systemctl To see all the loaded, active, and inactive units and their description, run this command: systemctl --all To see all the unit files and their current status but no description, run this command: systemctl list-unit-files The `grep` command filters the services by a search term, a helpful tactic to recall the exact name of a unit file without looking through a long list of names. Example: systemctl list-unit-files | grep network org.freedesktop.network1.busname static dbus-org.freedesktop.network1.service enabled systemd-networkd-wait-online.service enabled systemd-networkd.service enabled systemd-networkd.socket enabled network-online.target static network-pre.target static network.target For example, to list all the services that you can manage on Photon OS, you run the following command instead of `ls /etc/rc.d/init.d/`: systemctl list-unit-files --type=service Similarly, to check whether the `sshd` service is enabled, on Photon OS you run the following command instead of `chkconfig sshd`: systemctl is-enabled sshd The `chkconfig --list` command that shows which services are enabled for which runlevel on a SysVinit computer becomes substantially different on Photon OS because there are no runlevels, only targets: ls /etc/systemd/system/*.wants You can also display similar information with the following command: systemctl list-unit-files --type=service The following is list of some of the systemd commands that take the place of `SysVinit` commands on Photon OS: USE THIS SYSTEMD COMMAND INSTEAD OF THIS SYSVINIT COMMAND systemctl start sshd service sshd start systemctl stop sshd service sshd stop systemctl restart sshd service sshd restart systemctl reload sshd service sshd reload systemctl condrestart sshd service sshd condrestart systemctl status sshd service sshd status systemctl enable sshd chkconfig sshd on systemctl disable sshd chkconfig sshd off systemctl daemon-reload chkconfig sshd --add