Debian 12 Disk Full from Journal and Log 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

Root filesystem reaches 100 percent and applications fail to write data or start.

Environment & Reproduction

Common on long-running nodes with verbose logging and missing retention constraints.

Root Cause Analysis

Journal files and rotated logs accumulate faster than cleanup policy removes them.

Quick Triage

Free emergency space safely and identify top consumers before deleting operationally relevant logs.

Step-by-Step Diagnosis

Use df, du, journalctl –disk-usage, and logrotate state checks to locate growth sources.

Solution – Primary Fix

Vacuum journals, tune journald limits, and enforce logrotate retention for high-volume services.

Solution – Alternative Approaches

Ship logs centrally and reduce local verbosity for noncritical components.

Verification & Acceptance Criteria

Filesystem free space returns above threshold and log growth rate remains predictable.

Rollback Plan

Restore archived logs if required for compliance or incident investigation.

Prevention & Hardening

Set disk alerts, cap journal usage, and review noisy services quarterly.

Related Errors & Cross-Refs

No space left on device; journal file truncated; cannot write to log file.

Related tutorial: View the step-by-step tutorial for debian-12.

View all debian-12 tutorials on the Tutorials Hub →

Browse all common problems & solutions on the Tutorials Hub.

References & Further Reading

systemd-journald configuration docs, logrotate man page, and Debian operations guidance.