Re: Help with corrupt block

From: Jonathan Lewis <jonathan_at_jlcomp.demon.co.uk>
Date: Sat, 23 Nov 2002 16:43:10 -0000
Message-ID: <arobtl$cj8$3$8300dec7@news.demon.co.uk>

Notice that your output shows:

block X,Y corrupt
reread of block X,Y found valid data.

This suggests that you have a hardware problem, possibly around the controller somewhere, which is causing some zero-ed data to be passed to Oracle on a first read attempt, but (for statistical reasons) the second attempt reads the block properly.

An alternative to the bad hardware is that this is an 'error' thrown out by an RMAN process which tries to read a data block just as dbwr is writing it, and therefore see a fuzzy block and has to re-read it. In your case this interpretation is not the issue, as the head and tail checks match.

--
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Jonathan Lewis
http://www.jlcomp.demon.co.uk

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Alistair Thomson wrote in message ...


>Hi

>

>Oracle 8.1.7.0.0 EE

>NT 4 service pack 6e

>

>I have some very large partitioned tables. When trying to delete some

>records I was getting the following trace files and on two occassions

the


>server crashed! Nothing was showing in the alert log.

>

>I've searched through metalink but can't find anything of much use!

>

>The trace file contains information as shown below:

>

>*** SESSION ID:(14.37185) 2002-10-16 06:00:34.078

>***

>Corrupt block relative dba: 0x114042e3 (file 69, block 17123)

>Bad header found during buffer read

>Data in bad block -

> type: 6 format: 2 rdba: 0x114042db

> last change scn: 0x0000.54f4cd23 seq: 0x1 flg: 0x02

> consistency value in tail: 0xcd230601

> check value in block header: 0x0, block checksum disabled

> spare1: 0x0, spare2: 0x0, spare3: 0x0

>***

>Reread of rdba: 0x114042e3 (file 69, block 17123) found valid data

>***

>Corrupt block relative dba: 0x114101fa (file 69, block 66042)

>Bad header found during buffer read

>Data in bad block -

> type: 6 format: 2 rdba: 0x114101f2

> last change scn: 0x0000.557786e1 seq: 0x1 flg: 0x02

> consistency value in tail: 0x86e10601

> check value in block header: 0x0, block checksum disabled

> spare1: 0x0, spare2: 0x0, spare3: 0x0

>***

>Reread of rdba: 0x114101fa (file 69, block 66042) found valid data

>

>

>Any advice about what's going wrong here or how to fix it would be

>appreciated.

>

>Thanks

>

>Alistair

>

>

Received on Sat Nov 23 2002 - 10:43:10 CST