De-dupe Rate for MS_Exchange Data Stores

[Deepak_G]

We are backing up normal flat files seperately to a disk and exchange server data to another disk.

We dont have GRT enabled. The de-dupe ration for Flatfiles are closely to 60 %. But the de-dupe for Exchange server backup's are running at 4.69 %.

Need more ideas or suggestions on improving it.

[teiva-boy]

What version of Exchange?

I ask as Exch2010 does a maintenance task to defrag the database in real--time thus, high change rate = low dedupe rate.  Exch2k3/2k7 don't suffer this issue.  

You could try to change the segment size as well?

[MilesVScott]

Was this a 2010 issue? I'm wondering as we are looking to put our Exchange to dedupe pool as well. From everythnig I've read it is suggested that you sepperate Exchange to its own pool and "understand" that your rates will be much lower than regular file system backups.

[Deepak_G · Accepted solution]

Symantec Fix - solved the problem

http://www.symantec.com/business/support/index?page=content&id=TECH153190

This fix is applied for netbackup de-dupe servers. After applying it I am able to get good de-dupe rates now even on Exchange data stores which are bigger.

[MilesVScott]

So I take it you arent using Exchange 2010 then?

[Deepak_G]

Its actually exchange 2003.