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SC_DISK_ERR2: Serial number mismatch error logged on AIX or Virtual IO Server

Troubleshooting


Problem

Path failures occur for one or more LUNs/hdisks on AIX or Virtual IO Server.

Symptom

The AIX/ VIOS errpt log contains SC_DISK_ERR2 entry with Sense Data indicating 030F for the status validity and disk driver status fields.

Cause

The error occurs when an unspecified change on the storage side causes the LUN Serial Number previously provided to the host to be altered.
This typically involves some maintenance activity on the storage side.

Environment

AIX Server (all releases)
PowerVM Virtual IO Server (all releases)

Diagnosing The Problem

1. Download summ diagnostic tool on the server.
2. Examine errpt log as shown below.
errpt -a| summ

Oct 6 00:00:00 hdisk#  P SC_DISK_ERR2       path 2 INQUIRY         Serial number mismatch; Old: xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxold_number00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000; New: xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxnew_number00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000 (0 Sec rtry 01)
Oct 6 00:00:00 hdisk#  P SC_DISK_ERR2       path 1 INQUIRY         Serial number mismatch; Old: xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxold_number00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000; New: xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxnew_number00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000 (0 Sec rtry 01)
Oct 6 00:00:00 hdisk#  P SC_DISK_ERR2       path 0 INQUIRY         Serial number mismatch; Old: xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxold_number00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000; New: xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxnew_number00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000 (0 Sec rtry 01)

 
3. SC_DISK_ERR2 Serial number mismatch error shows an INQUIRY command sent to the storage device returned a New Serial Number that did not match the Old Serial Number previously reported by the same LUN. 
The error's Detailed Sense Data displays 030F as in the example below:
SENSE DATA
0600 1200 0000 FF00 0000 0000 0000 0000 0000 0000 0000 0000 030F 0000 3830 476E

Resolving The Problem

To resolve the errors from a changed disk serial number on AIX and VIOS, remove the affected hdisk and rescan using cfgmgr command to  rediscover the LUN:

# rmdev -dl hdisk#
# cfgmgr -l hdisk#
Need Further Assistance?
 
If the problem persists, please Open a case with IBM Support.
 

Document Location

Worldwide

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Document Information

Modified date:
21 July 2025

UID

ibm17172416