Lost Writes
From: Charlotte Hammond <charlottejanehammond_at_yahoo.com>
Date: Wed, 5 Aug 2009 14:29:08 -0700 (PDT)
Message-ID: <364902.59053.qm_at_web110106.mail.gq1.yahoo.com>
Hi All,
Date: Wed, 5 Aug 2009 14:29:08 -0700 (PDT)
Message-ID: <364902.59053.qm_at_web110106.mail.gq1.yahoo.com>
Hi All,
We recently had a�disk fault on one of our test servers.��After replacing the drive I recovered the database using RMAN only to encounter an ORA-600 [3020] part way relating to blocks in the system tablespace.� I had to do a point-in-time restore to get the database back.� We lost transactions (but since it was test not a big deal).
As�I understand�it this problem is possibly due to lost writes�(i/o not going�to disk but saying it has)�due to the disk drive going bad�(it may be due to other things, but lets assume that's the problem for the sake of discussion).� What I'm trying to understand is:
- Will this only�manifest itself�during a recovery or will I get a similar error if I try to update a stale block using SQL?
- Given I used the same backup but terminated the recovery earlier, presumably the stale block is still there, I just avoiding applying recovery to it.�� Do I now have a "bad" database? - should I exp/imp?� DBV shows nothing amiss but presumably these�will not be seen as logical corruptions as�the blocks are simply old, not badly formed.��������
- I see 11g can detect lost writes in conjunction with a standby.� Is there anything I can do on stand-alone 10g?� I'm now very paranoid I'll get the same thing in production and really loose data.
Thanks!
Charlotte
-- http://www.freelists.org/webpage/oracle-lReceived on Wed Aug 05 2009 - 16:29:08 CDT