Module 3. System Administration - Users, Packages, and Services

Duration: 6 hours

This module dives into the core daily tasks of a system administrator.

Topics Covered

This module is divided into the following detailed sections:

3.1 User and Group Management

• The “Big Three” files: /etc/passwd, /etc/shadow, /etc/group.
• Creating and modifying users (useradd, usermod).

3.2 Package Management

• Ubuntu/Debian: Using apt.
• Rocky/RHEL: Using dnf.

3.3 Service Management with Systemd

• Understanding Units.
• Using systemctl to start, stop, enable, and check status.

3.4 Logs and Monitoring

• Viewing logs with journalctl and traditional files in /var/log.
• Scheduling tasks with cron.