Links
:crescent_moon: Lab
:spiral_notepad: Tutorial
Details
Systemd is a collection of software components that manages Oracle Linux system services and settings. During system startup, the boot process initializes as PID 1, which systemd later manages. From there, systemd or one of its child processes starts all subsequent processes. Just like it is the first process to start after the system boots, it is the last to finish running when shutting down the system. Administrators and users use systemctl as the primary management tool to interact with systemd services and journalctl for troubleshooting.
Within systemd, different types of units manage various types of system behavior or functions. For example, daemon processes or system services are run as service units, while target units usually define system states. You also have timer units to schedule tasks, similar to how you might use the system cron service, and mount units to configure a mount point instead of configuring it in the system fstab.
While systemd manages all system-level processes and functions, it can also manage processes running in user space. Users can manage services and timers they create without administrator access and even configure them to continue after the user session has terminated.
Objectives
In this tutorial, you’ll learn to:
- Discover different systemd unit types
- Use systemd target units
- Run various systemctl commands
- Configure systemd to allow user space processes to run after logout
Prerequisites
Minimum of a single Oracle Linux system
Each system should have Oracle Linux installed and configured with:
- A non-root user account