Filesystem Full Under /var on RHEL 9

📖 ~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

Services fail to write logs or temporary files, and package operations report no space left.

Environment & Reproduction

Run df -h, du -xhd1 /var, and identify growth in logs, caches, containers, or crash dumps.

Root Cause Analysis

Unbounded journald data, package cache, container layers, or application log growth consumed /var.

Quick Triage

Vacuum journals, clear stale caches, rotate/compress logs, and prune unused container artifacts safely.

Step-by-Step Diagnosis

Capture top directories and service impact before cleanup actions.

Solution – Primary Fix

df -h shows restored free space and blocked services recover normal writes.

Solution – Alternative Approaches

Re-run failed operations and monitor space trend for at least one business cycle.

Verification & Acceptance Criteria

Set retention policies, log rotation limits, and storage alerts before critical thresholds.

Rollback Plan

Restore archived logs if accidental cleanup removed required audit data.

Prevention & Hardening

Schedule periodic cleanup for dnf cache and container leftovers with safeguards.

Related Errors & Cross-Refs

Use journalctl and application logs to correlate outages with storage saturation events.

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

Provide usage breakdown, cleanup actions taken, and any remaining blockers.