Re: corrupted block

  Metalink Note 130605.1 is worth reading about setting Maxcorrupt for an RMAN whole database backup (and checking alert.log for corruption messages).
Metalink Note 207413.1 describes RMAN incorrectly reporting block corruption.
Bugs 2068275, 1849726, and 1802432 may be interesting (upgrading Oracle 7 to Oracle 8i could contain a nasty surprise).

Have Fun :)

Ponnusamy wrote:

> I had the same belief that RMAN catches the corruption earlier, but
> not NOW.
>
> We had a database crash two months back and while performing the
> recovery(RMAN) one of the restored data file was corrupted. *BIG
> SHOCK* to everyone..We ran the dbverify on the restored files, the
> corruption showed up easily.. But not a single clue on the RMAN backup
> logs'.
>
> We asked Oracle Support, if rman checks for corruption in the data
> files when the data files are being backed up.. He said "No"..
>
> Oracle Ver: 8.1.7.2/Sun 2.6
>
>
> ..Ponnusamy
>
> At 11:40 AM 2/24/2003 -0800, DENNIS WILLIAMS wrote:
>
>> Stephen
>> RMAN ignored your corrupted block? Ya gotta tell us more man! We're
>> relying on it to catch everything. Did you have the MAXCORRUPT parameter
>> set?
>>
>> Dennis Williams
>> DBA, 40%OCP, 100% DBA
>> Lifetouch, Inc.
>> dwilliams_at_lifetouch.com
>>
>>
>> -----Original Message-----
>> Sent: Monday, February 24, 2003 11:45 AM
>> To: Multiple recipients of list ORACLE-L
>>
>>
>>
>> I think more recent versions of Oracle have options for skipping corrupt
>> blocks with exports.
>>
>> One possible way:
>> If you have a valid primary key index on the table, and the index is
>> in a
>> good tablespace, you might be able to cycle through all the primary
>> keys,
>> select the row corresponding to that primary key and insert it into a
>> new
>> table. I was able to do this about a month ago with a 8.1.7
>> database. In
>> my case, I think it was a block header that was corrupt, not data; so
>> I got
>> all the data OK. It was rather slow, grabbing and inserting one row
>> at a
>> time; but I got all the data. As long as I didn't do anything that
>> would
>> cause a table scan of any kind, I could get the data.
>>
>> By the way, rman not only failed to spot the corruption, but backed
>> it up
>> AND restored the corruption! My initial attempt was to just rename the
>> datafile at the file system level, then recover it from the previous
>> backup.
>> I could relate another one of those TAR non-support -- total and
>> complete
>> NON-support! -- on this one.
>>
>> > -----Original Message-----
>> >
>> > So my question is, if all backups contain the corrupted
>> > block, how would
>> > I copy all non-corrupted blocks from this table into a new table?
>> >
>> --
>> Please see the official ORACLE-L FAQ: http://www.orafaq.net
>> --
>> Author: Stephen Lee
>> INET: Stephen.Lee_at_DTAG.Com
>>
>> Fat City Network Services -- 858-538-5051 http://www.fatcity.com
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>> Please see the official ORACLE-L FAQ: http://www.orafaq.net
>> --
>> Author: DENNIS WILLIAMS
>> INET: DWILLIAMS_at_LIFETOUCH.COM
>>
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>
>

-- 
Please see the official ORACLE-L FAQ: http://www.orafaq.net
-- 
Author: Chip
  INET: ocp-dba_at_earthlink.net

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