DOCUMENT:Q158526  22-DEC-1999  [exchange]
TITLE   :XADM: .Pat Files in Mdbdata and Dsadata Directories
PRODUCT :Microsoft Exchange
PROD/VER:winnt:4.0,5.0,5.5
OPER/SYS:
KEYWORDS:kbusage exc4 exc5 exc55

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The information in this article applies to:

 - Microsoft Exchange Server, versions 4.0, 5.0, 5.5 
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SUMMARY
=======

You might find the following files when examining the contents of the Mdbdata
directory:

   Priv.pat
   Pub.pat

Likewise you might find this file in the Dsadata directory:

   Dir.pat

These files are created during the online backup process.

MORE INFORMATION
================

Patch files (.pat files) are created when doing an online backup of the Exchange
databases. These temporary files get created as soon as the backup process
begins; they contain whatever transactions take place during the online backup.
This way the Edb.log can be copied during the backup while transactions are
written to the patch files. The *.pat files are also copied to the hard disk
drive and replayed when a restore is done.

It is safe to delete these patch files if these two conditions apply:

 - There is no backup taking place.

 - There is no startup recovery in process after a restore.

Additional query words:

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Keywords          : kbusage exc4 exc5 exc55 
Technology        : kbExchangeSearch kbExchange500 kbExchange550 kbExchange400 kbZNotKeyword2
Version           : winnt:4.0,5.0,5.5

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