IBM AIX 7.3 – Common Problem 248 – 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

Cluster nodes drift seconds apart and Kerberos/db tickets start failing.

Environment & Reproduction

Triggered when /etc/ntp.conf points to unreachable servers or xntpd is not started.

Root Cause Analysis

xntpd is not synchronized; AIX uses local clock as time source.

Quick Triage

Run lssrc -s xntpd, ntpq -p, and date to compare hosts.

Step-by-Step Diagnosis

Check /etc/ntp.conf for server lines and /etc/rc.tcpip for xntpd entry.

Solution – Primary Fix

Add reachable servers, restart with stopsrc/startsrc -s xntpd, and verify ntpq -p reach > 0.

Solution – Alternative Approaches

Run ntpdate manually before starting xntpd to make a large step correction.

Verification & Acceptance Criteria

ntpq -p shows ‘*’ next to a peer and host time stays within 100ms of source.

Rollback Plan

Stop xntpd and revert /etc/ntp.conf from backup if new servers cause worse drift.

Prevention & Hardening

Use at least three internal NTP sources and monitor offset via nmon.

Related Errors & Cross-Refs

Linked to Kerberos and database authentication failures.

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 AIX 7.3 xntpd configuration and ntpq references.