Re: logical corruption

From: Bradd Piontek <>
Date: Fri, 23 May 2008 12:31:43 -0500
Message-ID: <>

Touching on the RMAN piece. Check out the Reference guide and look at the 'SET MAXCORRUPT" setting.

Tests data and index blocks that pass physical corruption checks for logical corruption, for example, corruption of a row piece or index entry. If RMAN finds logical corruption, then it logs the block in the alert.log and server session trace file.
Provided the sum of physical and logical corruptions detected for a file remain below its MAXCORRUPT setting, the RMAN command completes and Oracle populates V$DATABASE_BLOCK_CORRUPTION with corrupt block ranges. If MAXCORRUPT is exceeded, then the command terminates without populating the views.
Note: For COPY and BACKUP, the MAXCORRUPT setting represents the total number of physical and logical corruptions permitted on a file.

On Fri, May 23, 2008 at 12:24 PM, <> wrote:

> Hi List,
> env: Oracle Solaris 9
> v$database_block_corruption reported logical corruption for three
> datafiles.
> I ran "backup check logical validate database" which completed without
> any error.
> dbv also reported corruption for all three datafiles.
> I did not set maxcorrupt in RMAN so I assume it is set to default 0 (Is
> there any way to check this setting?)
> Last night RMAN full backup completed without any error.
> When I checked, corrupted blocks does not belong to any segment in two
> tablespaces to which these three files belong. (I used dbs_extents to map
> corrupted block to segment)
> This is production database so I am concerned.
> 1. Why "rman backup check logical validate database" does not report any
> error?
> 2. What are my options? I assume these blocks are marked as soft corrupt.
> Is there any way to repair/reclaim them?
> 3. Am I correct to assume that if I do not do any thing these blocks will
> not be used ever and will not cause any issue in future?
> Your valuable guidance is greatly appreciated.
> Thank you.
> Mayen

Bradd Piontek
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Received on Fri May 23 2008 - 12:31:43 CDT

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