Disk Full in /var Causing Service Outages

📖 ~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

A saturated /var partition can stop package operations, logging, and database services on Debian 9.

Environment & Reproduction

Applications fail to write logs, apt errors appear, and critical daemons enter crash loops.

Root Cause Analysis

Unbounded logs, runaway cache directories, retained core dumps, or backup jobs targeting local storage.

Quick Triage

Run df -h, du -xhd1 /var, and journalctl –disk-usage to identify largest consumers.

Step-by-Step Diagnosis

Image reference: 0. Include before-cleanup capacity and the largest directories by size.

Solution – Primary Fix

Image reference: 1. Display logrotate settings or service config adjusted to limit growth.

Solution – Alternative Approaches

Purge unnecessary logs and caches, compress archives, and free emergency space without deleting required data.

Verification & Acceptance Criteria

Set retention limits, configure alerts at 80 percent usage, and isolate high-churn data paths.

Rollback Plan

Confirm free space recovers and affected services restart cleanly with stable write behavior.

Prevention & Hardening

Recover removed files from backup if accidental deletion impacts service operation or audits.

Related Errors & Cross-Refs

Implement periodic cleanup tasks and storage trend reporting for legacy workload growth patterns.

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

View all debian-9 tutorials on the Tutorials Hub →

Browse all common problems & solutions on the Tutorials Hub.

References & Further Reading

Debian admin guide for filesystem capacity and log management best practices.