The ongoing-maintenance side of running a Linux system, once it's installed, configured, and online.

  • Backups

    A backup that's never been tested to restore isn't a backup - the 3-2-1 rule as a baseline strategy, and the standard Linux tools (rsync, tar) for actually implementing it.

  • Cron and Scheduled Tasks

    Two ways to run something on a schedule on Linux - the traditional cron daemon with its terse five-field syntax, and systemd timers as the newer systemd-native alternative.

  • Logs and journald

    Where Linux logs actually live and how to read them - journald's structured, queryable log on systemd systems, alongside the traditional plain-text files under /var/log that many tools still expect.

  • Monitoring and Performance

    The core commands for understanding what a Linux system is doing right now - CPU load, memory use, disk space, and which specific process is responsible.