Root filesystem reaches 100 percent usage

📖 ~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

Applications fail to write data, system updates fail, and services may crash due to no space.

Environment & Reproduction

RHEL 7 host with LVM-backed root partition where logs or temporary files grow uncontrolled.

Root Cause Analysis

Insufficient capacity planning, missing log rotation, or orphaned large files under /var.

Quick Triage

Check df -h and identify top consumers with du -xhd1 /var /opt /home.

Step-by-Step Diagnosis

Use lsof +L1 for deleted open files, inspect journalctl disk usage, and confirm LV/VG free extents.

Solution – Primary Fix

Clean safe temporary data, rotate logs, then extend LV with lvextend and resize2fs/xfs_growfs.

Solution – Alternative Approaches

Move high-growth paths to dedicated volumes and bind mount for better isolation.

Verification & Acceptance Criteria

Free space returns above threshold and failed services recover without write errors.

Rollback Plan

If extension fails, restore from snapshot and reapply only conservative cleanup changes.

Prevention & Hardening

Set alerts for disk usage and enforce logrotate policy across custom applications.

Related Errors & Cross-Refs

No space left on device, write failed, yum transaction aborted due to insufficient space.

Related tutorial: View the step-by-step tutorial for rhel-7.

View all rhel-7 tutorials on the Tutorials Hub →

Browse all common problems & solutions on the Tutorials Hub.

References & Further Reading

LVM Administration Guide, logrotate docs, RHEL 7 filesystem management references.