Storage and Backup | Microsoft Exchange Server 2003 Delta Guide

Every Exchange administrator has struggled with disaster recovery at one point or another. Over the years, Exchange administrators and backup software vendors have put several strategies into place to ensure that information held in Exchange could be recovered successfully in the case of an emergency.

With the introduction of Windows Server 2003 and the new Volume Shadow Copy Service (VSCS), neither Exchange administrators nor backup software vendors have to worry anymore.

The basic concept behind the VSCS is a point-in-time replication. Whenever a process is started to back up a particular drive, a snapshot of that drive and its contents is taken at that point in time. Instead of actually going back to the drive to perform a backup, the backup is performed off the point-in-time snapshot.

This eliminates the need to have exclusive use of a disk and has enabled backup software vendors to create innovative applications that don't require downtime or exclusive use of a resource. In practical application, this means that Exchange administrators can schedule more frequent backups without degrading messaging performance or even waiting for a backup "window" in the middle of the night. Backups can now occur any time of night or day.

BACKING UP EXCHANGE

You can use the Windows Backup utility that ships with Windows Server 2003 to back up Exchange, but it does not support backing up Exchange 2003 with VSCS. You can purchase a backup application that supports VSCS from any of the backup software providers (such as Veritas or Network Associates).

Another new feature that can be struck off the top of every Exchange administrator's wish list is a new Recovery Storage group that can restore Exchange Mailboxes.

You can use the Recovery Storage groups with your existing storage groups to move individual Mailboxes using the Exchange Mailbox Merge Wizard. This feature allows you to move Mailboxes to the appropriate location in your groups after you have finished the restore process.

This eliminates the techniques used in Exchange 2000, whereby an entire storage group had to be restored to get a single Mailbox. It also replaces a number of third-party tools that Exchange administrators used to employ to perform a single Mailbox recovery.

To set up a Recovery Storage group, follow these steps:

From the Exchange program group in the Start menu, open the Exchange System Manager and navigate to your server.
Right-click on the administrative group where you want to create your group and select New, Recovery Storage Group from the shortcut menu.
Specify a location in which to create this group, or accept the defaults and click OK.
Locate the group you just created and select Add Database to Recover from the shortcut menu. Then select a Mailbox store and click OK.
Open the Exchange Mailbox Merge Wizard (available in the Exchange 2003 Resource or at http://www.microsoft.com/exchange) and move the Mailbox you want to recover from its Recovery Storage group to the appropriate storage group location.

Following these steps enables you to quickly back up and recover Mailboxes for users without having to use any of the third-party tools mentioned earlier.

RESTORING DIRECTLY TO THE ORIGINAL STORAGE GROUP

If you want to restore a Mailbox to the same storage group in which it was originally stored, you need to edit the registry on the server you are working on. Locate the HKLM\SYSTEM\CurrentControlSet\Services\MSExchangeIS\ParametersSystem key and add a new value of Recovery SG Override and set it to 1. This setting tells the Exchange Backup API to ignore the presence of the RSG when using backup products so that the Mailboxes will be recovered to their original location. You can now move Mailboxes you have recovered to their original location.