Managing services with `systemd` is a skill that modern Linux system administrators require to enable or disable processes to run as a service on the system. Being able to troubleshoot systemd services is invaluable for correct system operation. In this activity, you will learn about managing systemd services by troubleshooting why a oneshot systemd service is failing. Once this activity is complete, you should be comfortable managing `systemd` services with `systemctl`.
Learning Objectives
Successfully complete this lab by achieving the following learning objectives:
- Use systemctl to check the status of target.service. Update the systemd oneshot service unit file named target.service.
Using
systemctl
check the status of thetarget.service
.systemctl status target.service systemctl status -l target.service
Using the editor of your choice, update the
/etc/systemd/system/target.service
file to match the following contents.[Unit] Description=Log when default target reached After=cloud-final.service [Service] Type=oneshot RemainAfterExit=yes ExecStart=/bin/echo "---> Reached default.target" ExecStart=/bin/ls -l /etc/systemd/system/default.target [Install] # WantedBy is similar to runlevel WantedBy=default.target
- Reload the `systemd` daemon for updated unit file to be available. Check to see if service will start.
Use the
systemctl
command to reload thesystemd
daemon, so the new unit file can be managed.systemctl daemon-reload
Use the
systemctl
command to start and check status of thetarget.service
.systemctl start target.service systemctl status target.service
- Enable the `target.service` and reboot system.
Using the
systemctl
command enable thetarget.service
and reboot the system to verify operation of service at boot time.systemctl enable target.service reboot
- Reconnect to system and check the status of the `target.service`.
First, you will need to use your lab credentials to reconnect to the system and access the root account. Then, use the
systemctl
command to view the status of thetarget.service
. It should show that thetarget.service
started correctly.sudo -i systemctl status target.service