IBM AIX 7.3 – Common Problem 115 – 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

drmgr -c cpu -a fails with ‘busy’ or driver error.

Environment & Reproduction

HMC requests CPU add but RMC link to LPAR is down.

Root Cause Analysis

Resource Monitoring and Control (rsct) services not running.

Quick Triage

Run lssrc -a | grep -i rmc and rmcdomainstatus -s ctrmc.

Step-by-Step Diagnosis

Inspect /var/ct/IW/log/mc/IBM.DRM logs for refusal reason.

Solution – Primary Fix

Restart RMC: /usr/sbin/rsct/bin/rmcctrl -A then retry from HMC.

Solution – Alternative Approaches

Reboot the LPAR to refresh device drivers if RMC OK but driver stuck.

Verification & Acceptance Criteria

lparstat -i shows new CPUs online and entitlement updated.

Rollback Plan

Reduce CPUs with drmgr -c cpu -r if instability follows.

Prevention & Hardening

Open HMC firewall for RMC ports and document baseline.

Related Errors & Cross-Refs

Pairs with similar ‘memory add fails’ DLPAR cases.

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: RSCT, RMC, drmgr.