IBM AIX 7.3 – Common Problem 021 – 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 logs show timestamps drifting and xntpd reports peer unreachable.

Environment & Reproduction

IBM AIX 7.3 LPAR exhibiting Time sync / xntpd drift issues under standard PowerVM workloads.

lssrc -s xntpd
ntpq -p

Root Cause Analysis

Firewall blocks UDP 123 or xntpd peer entries reference decommissioned servers.

Quick Triage

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

ntpq -p
cat /etc/ntp.conf

Step-by-Step Diagnosis

Check xntpd status and peer reachability.

lssrc -s xntpd
ntpq -pn

Solution – Primary Fix

Update /etc/ntp.conf with valid peers and restart xntpd.

stopsrc -s xntpd
startsrc -s xntpd

Solution – Alternative Approaches

Switch to chrony or one-shot ntpdate via cron if drift persists.

Verification & Acceptance Criteria

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

ntpq -p
date

Rollback Plan

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

stopsrc -s xntpd

Prevention & Hardening

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

smit xntpd  # monitor stratum and offset

Related Errors & Cross-Refs

errpt LABEL=XNTPD_*; clock skew

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

AIX time services configuration