Ubuntu 18.04 LTS system runs out of disk space in /var

📖 ~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 temp data due to full partition.

Environment & Reproduction

Busy host with high log volume and package cache accumulation.

Root Cause Analysis

Unbounded logs, crash dumps, and stale cache consume /var rapidly.

Quick Triage

Identify largest directories and immediate write-failure scope.

Step-by-Step Diagnosis

Use du and journalctl disk-usage tools to pinpoint growth sources.

Solution – Primary Fix

Clean caches, rotate logs, and expand filesystem where possible.

Solution – Alternative Approaches

Relocate bulky paths to dedicated volume with bind mounts.

Verification & Acceptance Criteria

Sustained free space and normal write operations confirmed.

Rollback Plan

Undo mount changes and restore prior log retention if needed.

Prevention & Hardening

Set quotas, retention limits, and proactive disk usage alerts.

Related Errors & Cross-Refs

Differentiate inode exhaustion from pure capacity depletion.

Related tutorial: View the step-by-step tutorial for Ubuntu 18.04 LTS.

View all Ubuntu 18.04 LTS tutorials on the Tutorials Hub →

Browse all common problems & solutions on the Tutorials Hub.

References & Further Reading

Ubuntu storage management and logrotate operational guidance.