IBM AIX 7.3 – Common Problem 017 – 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

SSH logins hang after openssh upgrade; sshd reports PAM failures in errpt.

Environment & Reproduction

IBM AIX 7.3 LPAR exhibiting SSH / openssh fileset issues under standard PowerVM workloads.

lslpp -L openssh.base
lssrc -s sshd

Root Cause Analysis

PAM stack misconfigured after openssh fileset update on AIX 7.3.

Quick Triage

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

lssrc -s sshd
cat /etc/ssh/sshd_config

Step-by-Step Diagnosis

Inspect /etc/pam.conf and sshd_config for UsePAM and auth stack issues.

lssrc -s sshd
grep UsePAM /etc/ssh/sshd_config

Solution – Primary Fix

Restore default PAM stack and restart sshd.

cp /etc/pam.conf.bak /etc/pam.conf
stopsrc -s sshd && startsrc -s sshd

Solution – Alternative Approaches

Roll back openssh fileset to previous level via installp -u.

Verification & Acceptance Criteria

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

ssh -V
lssrc -s sshd

Rollback Plan

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

installp -u openssh.base

Prevention & Hardening

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

smit installp  # commit only after verification

Related Errors & Cross-Refs

errpt LABEL=SSHD_PAM_AUTH; auth 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

AIX OpenSSH packaging notes