Microsoft KB Archive/232938

= The "Last Backup Set" check box and hard recovery in Exchange =

Article ID: 232938

Article Last Modified on 12/3/2007

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APPLIES TO


 * Microsoft Exchange Server 2003 Enterprise Edition
 * Microsoft Exchange Server 2003 Standard Edition
 * Microsoft Exchange 2000 Server Standard Edition
 * Microsoft Windows Small Business Server 2003 Premium Edition
 * Microsoft Windows Small Business Server 2003 Standard Edition

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This article was previously published under Q232938



SUMMARY
When you restore an Exchange database, you have the option to indicate that the restore procedure that you are performing is the last restore procedure you will perform before you mount the database. This option is enabled by clicking to select the Last Backup Set check box after you click the Start Restore button on the Restore tab in Microsoft Windows 2000 Backup.

This article explains the effects of enabling this option.



MORE INFORMATION
When you restore an online backup of an Exchange database, the database is in an inconsistent state. The process of bringing the database to a consistent state after a restore procedure is called "hard recovery." During hard recovery, the Extensible Storage Engine (ESE) uses information in the log files and patch files to redo operations performed on the database and then to undo any operations that belong to incomplete transactions.

In earlier versions of Exchange Server, this happens automatically the next time the service started. When the service starts, the presence of a Restore in Progress registry key indicates that recovery must be run on the database using the information in the Restore in Progress key.

In Exchange, hard recovery is no longer controlled by the Restore in Progress key. It is controlled by a file called Restore.env that is created in the folder that you specify during the restore process in the Temporary location for log and patch files box. This folder will also contain the log files and patch (.pat) files necessary to complete recovery on the database.

Note If you are running Microsoft Exchange 2000 Server Service Pack 2 (SP2) or a later version of Microsoft Exchange 2000 Server, you will not have any patch files (.pat files) after the restore.

The Last Backup Set check box in Windows 2000 Backup determines if hard recovery should be run after the backup completes. If you select this check box, hard recovery is run automatically after the restore procedure finishes, and then the temporary files are removed. At this point, you can mount the database. If you don't select this check box, hard recovery is not run. After the database files and temporary files are copied to disk, the restore procedure finishes. If you attempt to mount the database at this point, you will not be able to.

The purpose of the Last Backup Set option is to allow you to restore a full backup, and then restore one or more incremental backups or a differential backup. You only select this check box during the last restore procedure because you do not want hard recovery to run until all the log files to be recovered are in place.

For example, if you are restoring an Exchange database from a full backup and two incremental backups, click to clear the Last Backup Set check box when you restore the full and the first incremental backups. Click to select the Last Backup Set check box only for the last incremental backup.

In certain circumstances, you may not want to run hard recovery immediately after the restore procedure. Also, you may forget to select the Last Backup Set check box during the last restore procedure. For these reasons, you can manually run hard recovery using the Eseutil.exe utility.

Use the following command to manually run hard recovery:

eseutil /cc

For example, if the path specified in the Temporary location for log and patch files box during the restore procedure is C:\TempRest, the command to run hard recovery is:

eseutil /cc c:\temprest\

Note You must run Eseutil.exe from the Exchsrvr\Bin folder.

Additional query words: pt logs ese jet logging transaction commit hard recovery logfile XADM

Keywords: kbinfo KB232938

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