📖 ~1 min read
Table of contents
Symptom & Impact
After update LPAR fails to boot with LED 0c31 or similar code.
Environment & Reproduction
bosboot was not run after kernel-level fileset updates on AIX 7.2.
Root Cause Analysis
Boot logical volume hd5 not in sync with the kernel image.
Quick Triage
Boot from NIM or installation media in maintenance mode (option 3).
Step-by-Step Diagnosis
Use getrootfs hdiskN and bosboot -a -d /dev/hdiskN to rebuild the BLV.

Solution – Primary Fix
Run bosboot -a -d /dev/hdiskN then bootlist -m normal hdiskN to refresh.
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Solution – Alternative Approaches
Restore the BLV from an alt_disk_copy clone if bosboot still fails.
Verification & Acceptance Criteria
LPAR boots normally and lscfg shows the correct boot list and kernel level.
Rollback Plan
Set bootlist back to the alt_disk_copy clone to roll back kernel updates.
Prevention & Hardening
Always run bosboot -a after kernel updates and verify with bootlist.
Related Errors & Cross-Refs
Often pairs with bosboot warnings during installp commit.
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: bosboot, bootlist, alt_disk_install maintenance.
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