IBM AIX 7.3 – Common Problem 149 – Diagnosis and Fix

📖 ~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

`touch` fails with `ENOSPC` on `/var/spool` even though `df -k` shows plenty of free blocks.

Environment & Reproduction

AIX 7.3 host whose `/var/spool` was created with a small `nbpi` value years ago.

Root Cause Analysis

Per-inode density (`nbpi`) is too low; the filesystem is out of inodes despite free space.

Quick Triage

Run `df -kI /var/spool` to compare used vs free inodes and `lsfs -q /var/spool` for nbpi.

Step-by-Step Diagnosis

Identify small-file hotspots with `find /var/spool -xdev -type f | wc -l` and `du -ks`.

Solution – Primary Fix

Increase inodes via `chfs -a nbpi=2048 /var/spool` (requires fs grow and remount).

Solution – Alternative Approaches

Recreate `/var/spool` on a larger LV: `mklv`, `crfs -v jfs2 -a nbpi=2048` and restore data.

Verification & Acceptance Criteria

`df -kI /var/spool` shows free inodes >50% and `touch` succeeds.

Rollback Plan

Restore from `mksysb` or `tar` backup if the chfs operation corrupts metadata.

Prevention & Hardening

Set `nbpi=4096` (or smaller) for high-density spool filesystems at creation time.

Related Errors & Cross-Refs

Pairs with `J2_INODES_FULL` errpt and `sendmail`/`cron` queue stalls.

Related tutorial: View the step-by-step tutorial for aix-7.3.

View all aix-7.3 tutorials on the Tutorials Hub →

Browse all common problems & solutions on the Tutorials Hub.

References & Further Reading

IBM Docs: JFS2 `nbpi`, `chfs`, `crfs` filesystem sizing.