Exchange 2000 .ifs files and 16GB IS limitation

Posted on 2007-03-21
Last Modified: 2010-08-05
I ran into a problem with a customer yesterday where they actually hit the 16GB limit (I think) in Exhange 2000.  I had a couple of questions about this, mostly so I'm better armed for next time.

First, I have temporarily resolved this issue by using the registry fix that increases the temp size from 16GB to 17GB.  The initial symptom was that the IS wouldn't mount properly.  It would mount, but then immediately dismount as soon as someone tried to access it.  Now that the limit is up to 17GB it mounts and users can get in.

But I think part of the reason I missed this is that I was only keeping an eye on the size of the priv1.edb file in the MDBDATA directory.  Yesterday it was a little over 12GB, which didn't seem close enough to be a real concern.  But when it crashed I began to wonder if the actual size of the store is the priv1.edb + priv1.stm.  Because the priv1.stm file is a little over 4GB the two together would explain exceeding the 16GB limit.  Can anyone confirm whether this is correct?  Does the limit refer to the two together?

Also, as soon as the IS crashed the server started populating my MDBDATA directory with "IFS Files" ending in .ifs (for example, "FB7-8836B820-2E9F739.IFS").  I haven't seen these before.  Can anyone tell me what they are?  Will they go away on their own eventually?  Can I just delete them?


Question by:cns13
LVL 35

Accepted Solution

rakeshmiglani earned 125 total points
ID: 18763114
the database size is calculated as edb+stm
regarding IFS files, you can check the following
LVL 13

Assisted Solution

vishal_breed earned 125 total points
ID: 18763141
* Exchange 2000 (standard edition) can support only till 16 GB - ofcourse 17 GB registry option is to resolve 16 GB problem. So that you mount the database - remove emails - run online maintainance & then offline defrag.

* Since Exchange 2003 SP2; 16 GB limit is increased till 75 GB!!

* 16 GB is considered as SUM of priv1.edb + priv1.stm. (same with Public Folders).

* About .ifs file have look at
It says, .ifs files are temporary files that are used during the normal operation of the Information Store service to cache directory listings and Exchange Installable File System (IFS) Master File Table (MFT) listings. The .ifs files are created with the FILE_FLAG_DELETE_ON_CLOSE flag set. The Information store process automatically deletes these files, and if any .ifs files are accidentally left behind (if the server stops responding, for example), they should all be deleted when the Information Store service starts. It is dangerous to delete .ifs files manually when Information Store service is running, but you can delete them safely when that service is not running.


Author Comment

ID: 18763293
Thanks guys.  I appreciate the help.

Now I get the fun part of explaining to users that they can't all have 1.6GB mailboxes.  They fought hard against my imposing limits.  Now I get to tell them either live with the limits or shell out $$$ to go to 2003.

That'll go over well.


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