detecting corruption of exchange db

[maverick964uk]

Hi,

Most backup products do not perform any level of database consistency before backing up, therefore they will backup a corrupted db.

What can be done with an exchange 5.5 db to check this and highlight corruption??.

What advantages are there with exchange 2000 and 2003?.

thanks
Mike

 

[zbnet]

Online (Exchange-aware) backups run a page-level integrity check on your database, this will cause the backup to fail when the database is corrupt. This will be accompanied by errors in the event log, look for 166 or 200 events from a source of ESE97.

So long as you check your backups every morning, and investigate any errors in the event logs, you'll be safe. Recovery is as simple as restoring the last good database backup, which when you start the IS service will replay all the still-on-disk transction logs and bring the database slap up to date with no data loss.

 

[maverick964uk]

Hello,

thanks for the reply.

The product being used is HP Omniback and is a certified microsoft backup product. Also like other products, exchange provides the backup API so that tools like omniback can interact to kick off online backups. This would be the same for veritas and others.

I would presume that exchange is performing the checks?.

I will review the event logs........

thanks

 

[muffinresearch]

One thing to bear in mind (presumably you are running this on NT) is that NT suffers from a problem where cached data is not always written to disk.

the symptoms of this are accompanied by the following:

Event ID 41.
The file system structure on the disk is corrupt and unusable. Please run the Chkdsk utility on the volume "Name".

There is a fix for this and it can help to stop your exchange databases from corrupting.

http://support.microsoft.com/default.aspx?scid=kb;en-us;310841

One point worth mentioning is that if you have previously repaired corrupted databases they often recorrupt. The best plan is to use exmerge to copy mail into psts and then import it all back into a fresh set of databases.

 

[zbnet]

Exmerging an entire store out and then back into a new one can take some time. It also breaks the single instance storage, which can make quite a big difference to the size of priv.edb, depending on the typical recipient profile of mail that is send on the server.

 

[maverick964uk]

Guys,

many thanks for your replies. Most helpful.

I imagine that upgrading to win2k and exchange 2000 will help!?

Regards,
Mike