ORA-27091 and DB corruptions when using VxVM as ASM disks in AIX platform

(Doc ID 1348119.1)

Last updated on JULY 05, 2017

Applies to:

Oracle Server - Enterprise Edition - Version: to - Release: 10.1 to 11.2
IBM AIX on POWER Systems (64-bit)
IBM AIX on POWER Systems (32-bit)


Customer had space issues. To fix the space issue, then clean up the diskgroup and ran diskgroup rebalance. Then there were some IO errors during the rebalance. After that, customer started getting DB corruption errors in DB alert log like the followings.

Hex dump of (file 185, block 2575615) in trace file
Corrupt block relative dba: 0x2e674cff (file 185, block 2575615)
Fractured block found during backing up datafile
Data in bad block:
type: 6 format: 2 rdba: 0x2e674cff
last change scn: 0x098f.a8e6414c seq: 0x1 flg: 0x04
spare1: 0x0 spare2: 0x0 spare3: 0x0
consistency value in tail: 0x0e5c0601
check value in block header: 0x8985
computed block checksum: 0x9e4f
Sat Jul 16 19:22:24 2011
Errors in file /u01/u0001/oracle/admin/<dbname>/udump/<dbname>_ora_1507392.trc:
ORA-27091: unable to queue I/O
ORA-27072: File I/O error

This DB block could not be recovered by regular block recovery method due to the IO errors.
When using dd command to dump the corrupted block, found the block was located at the very last block of an ASM disk and the block content was incomplete.


Sign In with your My Oracle Support account

Don't have a My Oracle Support account? Click to get started

My Oracle Support provides customers with access to over a
Million Knowledge Articles and hundreds of Community platforms