Chapter 15: Scripts and scheduling

Write shell scripts with arguments, tests and loops, and schedule them with cron, systemd timers and at.

What you will learn

• Write and run a bash script, with variables, arguments and exit statuses.
• Use tests, if, case, for and while to make a script decide and repeat.
• Schedule jobs with crontab and /etc/cron.d, and diagnose cron problems from its log.
• Create systemd timers and one-off at jobs, and choose the right scheduler.

Sections

1. Your first shell scripts
2. Exercise: Write and run your first scripts
3. Decisions and loops
4. Exercise: Scripts that decide and repeat
5. Scheduling jobs with cron
6. Exercise: Schedule a job
7. systemd timers and one-off jobs
8. Exercise: Timers and one-off jobs
9. Exercise: Scripts and scheduling review
10. Bash scripts and scheduling quiz
11. Bash scripts and scheduling cheat sheet