Knowing how to use `systemctl` is one of the most important and foundational skills to have when managing systemd-based systems. The `systemctl` utility is used for so many tasks and contains such a large amount of subcommands that it can be slightly intimidating at first for those familiar with individual commands for most management tasks.
In this lab, we’ll get you used to using `systemctl` to view systemd’s environment, settings, view status on services, show and set parameters that affect service function, and understand what happens when you set settings, both from a `systemd` daemon perspective, as well as drop-in directories and additional configuration add-ins.
You’ll come out of this lab feeling more confident with `systemctl` than ever and ready to start managing your systemd-based systems right away!
Successfully complete this lab by achieving the following learning objectives:
- Investigate the systemd Environment and Service Status
- Show the systemd environment.
- View service status.
- Become familiar with the systemd directory contents and query and display service parameters.
- Install a systemd-Managed Service and Change Its Parameters
- Install CUPS
- View its status and start and stop the service
- Change a service parameter and find out what changed as a result
- Reverse a Parameter Change to a Service
- You’ll stop the service, remove the setting, change directory, and override files, reload systemd’s daemon and restart the service, and confirm it is back to factory settings.