IBM AIX 7.2 – Common Problem 070 – 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

AIX LPAR time drifts >5 minutes from NTP source; xntpd shows ‘no server suitable’.

Environment & Reproduction

xntpd on 7.3 cannot reach upstream NTP servers behind firewall.

Root Cause Analysis

UDP/123 blocked or NTP server pool unresolved on this LPAR.

Quick Triage

Run lssrc -s xntpd and ntpq -p to view peers.

Step-by-Step Diagnosis

Use ntpdate -q to test reachability without changing time.

Solution – Primary Fix

Switch to chrony equivalent (timed) or fix UDP/123 firewall rules.

Solution – Alternative Approaches

Force one-off sync with ntpdate -u then restart xntpd.

Verification & Acceptance Criteria

ntpq -p shows reach=377 and offset within +/- 50ms.

Rollback Plan

Revert /etc/ntp.conf from backup and restart xntpd.

Prevention & Hardening

Use at least 3 internal NTP peers and monitor offset.

Related Errors & Cross-Refs

Time-sensitive Kerberos failures, log timestamp skew.

Related tutorial: View the step-by-step tutorial for aix-7.2.

View all aix-7.2 tutorials on the Tutorials Hub →

Browse all common problems & solutions on the Tutorials Hub.

References & Further Reading

AIX xntpd / NTP configuration documentation.