IBM AIX 7.3 – Common Problem 007 – 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

Application writes fail with ENOSPC even though df shows free blocks.

Environment & Reproduction

IBM AIX 7.3 LPAR exhibiting filesystem inode exhaustion issues under standard PowerVM workloads.

df -g
df -v

Root Cause Analysis

JFS2 inode allocation hits the per-filesystem limit because of many small files.

Quick Triage

Confirm scope with errpt, recent changes, and subsystem state via lssrc.

df -v
istat /var

Step-by-Step Diagnosis

Use df -v to confirm inode usage and identify offending directory.

df -v
find /var -type f | wc -l

Solution – Primary Fix

Increase the inode allocation with chfs nbpi or recreate with smaller nbpi.

chfs -a nbpi=1024 /var

Solution – Alternative Approaches

Migrate small-file workloads to a new filesystem sized with proper nbpi.

Verification & Acceptance Criteria

Confirm subsystem returns to RUNNING state and errpt shows no new entries.

df -v /var

Rollback Plan

Restore prior configuration from mksysb or alt_disk_install clone if the fix regresses.

chfs -a nbpi=4096 /var  # only at create time

Prevention & Hardening

Encode the fix in NIM customisation scripts and monitor via topas/nmon.

smit chjfs2  # plan nbpi when creating new FS

Related Errors & Cross-Refs

errpt LABEL=JFS2_INODE; ENOSPC despite free blocks

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

JFS2 sizing and nbpi tuning