Root Filesystem Near Full Due to /var Growth

📖 ~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

System reports no space left on device and services fail to write temporary files.

Environment & Reproduction

Unrotated logs, crash dumps, package cache growth, or runaway application output.

Root Cause Analysis

Use df -h and du -xhd 1 /var to locate major consumers quickly.

Quick Triage

Purge safe temporary files and rotate logs to recover immediate headroom.

Step-by-Step Diagnosis

Run du -xhd 1 /var | sort -h and clear stale pkg cache with pkg clean -ay.

Solution – Primary Fix

Check app and syslog retention policies to identify unbounded growth settings.

Solution – Alternative Approaches

Implement rotation, cap retention, and migrate heavy data to dedicated ZFS datasets.

Verification & Acceptance Criteria

Ensure free space remains stable over 24 hours under normal workload.

Rollback Plan

Add disk alerts and weekly housekeeping tasks for logs and caches.

Prevention & Hardening

Restore accidentally removed files from backup snapshots if needed.

Related Errors & Cross-Refs

Escalate if unexplained growth continues, suggesting app leak or attack activity.

Related tutorial: View the step-by-step tutorial for freebsd-15.

View all freebsd-15 tutorials on the Tutorials Hub →

Browse all common problems & solutions on the Tutorials Hub.

References & Further Reading

df -h; du -xhd 1 /var; pkg clean -ay; newsyslog -Fv