Re: data block corrupted: how to repair ?

Frank Langelage <frank_at_lafr.de> wrote in message news:<bu77u6$e8qot$1_at_ID-48907.news.uni-berlin.de>...
> my oracle instance won't start anymore. I get the following messages:
>
> Corrupt block relative dba: 0x00800039 (file 2, block 57)
> Fractured block found during buffer read
> Data in bad block -
> type: 38 format: 2 rdba: 0x00800039
> last change scn: 0x0000.08269b3c seq: 0x1 flg: 0x04
> consistency value in tail: 0x00009b3c
> check value in block header: 0xccd9, computed block checksum: 0xafb3
> spare1: 0x0, spare2: 0x0, spare3: 0x0
> ***
> Reread of rdba: 0x00800039 (file 2, block 57) found same corrupted data
> ORA-01578: ORACLE data block corrupted (file # 2, block # 57)
> ORA-01110: data file 2: '/oratemp/PROD/undotbs01.dbf'
>
> How to get the instance up and running again ?
>
> Is there a way other than recreate the instance and importing data ?
>
>
> Regards
>
> Frank

Frank, it appears to me that you are using Oracle managed rollback and one of the rollback segments is corrupted. I would open an iTAR with Oracle and get the name of the current underbar parameter that will start the database skipping corrupted rollback segments.

Another option might be to recover the undo/rollback tablespace from your last hot backup and then roll forward to see if you can recover without recreating the corruption. Depending on the nature of the corruption a roll forward recovery might recreate the corruption or it might fix the block.

Knowing what happened prior to the corruption might be important to determing the next step to take: normal shutdown, instance crash, hardware failure, etc...

HTH -- Mark D Powell -- Received on Fri Jan 16 2004 - 07:53:34 CST