Systemd Timer Not Triggering Scheduled Maintenance Job

📖 ~1 min read

Table of contents

1. Symptom & Impact
2. Environment & Reproduction
3. Root Cause Analysis
4. Quick Triage
5. Step-by-Step Diagnosis
6. Solution – Primary Fix
7. Solution – Alternative Approaches
8. Verification & Acceptance Criteria
9. Rollback Plan
10. Prevention & Hardening
11. Related Errors & Cross-Refs
12. References & Further Reading

Symptom & Impact

Maintenance script never runs even though timer files exist.

Environment & Reproduction

Use systemctl list-timers –all and systemctl status .

Root Cause Analysis

Check if timer is disabled, mis-scheduled, or service unit failed.

Quick Triage

Timer not enabled, wrong OnCalendar syntax, or unit naming mismatch.

Step-by-Step Diagnosis

Validate unit names and OnCalendar using systemd-analyze calendar.

Solution – Primary Fix

Run systemctl daemon-reload, enable –now timer, and monitor next trigger.

Solution – Alternative Approaches

Confirm linked service exits successfully when manually started.

Verification & Acceptance Criteria

If job depends on remote API, ensure egress rules allow it.

Rollback Plan

Check SELinux denials if timer runs custom scripts in restricted paths.

Prevention & Hardening

journalctl -u and -u reveal schedule and execution errors.

Related Errors & Cross-Refs

Add timer status checks to host monitoring and compliance audits.

Related tutorial: View the step-by-step tutorial for rhel-9.

View all rhel-9 tutorials on the Tutorials Hub →

Browse all common problems & solutions on the Tutorials Hub.

References & Further Reading

Revert to prior timer unit versions and reload systemd.