IBM AIX 7.1 – Common Problem 118 – 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 clock jumps and Kerberos auth fails intermittently.

Environment & Reproduction

AIX 7.2 LPAR using xntpd with an unreachable or asymmetric NTP peer.

Root Cause Analysis

Peer offset exceeds the panic threshold or xntpd is not running.

Quick Triage

Run lssrc -s xntpd and ntpq -pn to inspect peer status.

Step-by-Step Diagnosis

Look for ‘no server suitable for synchronization’ in /var/adm/messages.

Solution – Primary Fix

Restart with stopsrc -s xntpd; startsrc -s xntpd and confirm peers reach.

Solution – Alternative Approaches

Switch to chrony equivalents or fix /etc/ntp.conf server entries.

Verification & Acceptance Criteria

ntpq -pn shows a ‘*’ selected peer and offset/jitter under thresholds.

Rollback Plan

Restore the original ntp.conf if a new peer is unreliable.

Prevention & Hardening

Use at least three peers and monitor offset via nmon or custom checks.

Related Errors & Cross-Refs

Pairs with KRB5KDC_ERR_PREAUTH_FAILED auth failures.

Related tutorial: View the step-by-step tutorial for aix-7.1.

View all aix-7.1 tutorials on the Tutorials Hub →

Browse all common problems & solutions on the Tutorials Hub.

References & Further Reading

IBM Docs: xntpd, ntp.conf on AIX 7.2.