In Exchange 2010 Mailbox Server Backup and Restore Part1 we completed the backup procedure. In Exchange 2010 Mailbox Server Backup and Restore Part2 we completed the restore process and learned how to restore an email item. In this article we will learn how to use the same backup files to perform the following recovery operations:

• Recover a user mailbox

• Recover a mailbox database

• Recover a server

As stressed in the previous articles, our recovery scenarios will not make use of the deleted mailbox retention configured at the mailbox database. Instead we will assume that the mailbox has been deleted and the deleted mailbox retention period has also expired. In this case, the only place from where we can recover our mailbox is the backup.

Recovering a Mailbox

We have already mentioned that Windows Server Backup does not have an option for single mailbox recovery, so we must first recover the complete database, and then extract the user mailbox from the database.

Recovering an Exchange Server database was described in Part 2, where we used the Recovery Database.

In order to restore a mailbox, we should run the following cmdlet:
Restore-Mailbox -Identity Vladimir -RecoveryDatabase RDB1

Once we complete this cmdlet, we will see the mailbox presence from the Exchange Management Console.

If we need to restore all mailboxes located in the Managers database, we should run the cmdlet:
Get-Mailbox -Database Managers | Restore-Mailbox -RecoveryDatabase RecoveryDB

Note that this applies to the case where only the mailbox was removed, whereas the Active Directory user account still exists. If the user was also removed from AD, then we should first create the user account, recover the mailbox and connect the user to the mailbox.

Recovering a Mailbox Database

Due to the different type of failures, such as hardware failures, there are situations when the database has to be restored completely.

Let's assume the database went lost for some reason. When we open the Exchange Management Console and the database is shown as dismounted, attempting to mount the database displays the message:

On this dialog we are going to click No.

Before starting the restore procedure, we should enable database overwriting from the Exchange Management Console, as shown here:

The same could be performed using the Exchange Management Shell cmdlet:
Set-MailboxDatabase -Identity "Managers" -AllowFileRestore $true

In order to restore the database, we initially follow a procedure similar to the one described in the previous article part, with the exception of:

• We are not going to use the Recovery Database

• In Windows Server Backup, at the Recovery Wizard | Specify Recovery Options page, we choose "Recover to original location", as shown:

Important: By selecting this option, we will not be able to choose which database to recover to its original location. If the backup file contains multiple databases, all of them will be recovered to their respective original location. In our example, we will assume that we have a backup strategy that creates a separate backup file for each database.

Finally, at the confirmation page, we choose Recover and wait for the recovery progress success notification.

So far we have restored the exchange database files to their original location. Next step is to mount the database using the Exchange Management Console or Shell with the cmdlet:
Mount-Database -Identity "Managers"

Now the users will again have access to their mailboxes on the recovered and healthy database.

Recovering a Mailbox Database using Dial Tone Recovery

In the previous restore scenario, the database was dismounted and was not accessible to users, so they could not read or send emails. The restore process could take a considerably long time, depending on the database size.

Waiting for the database restore process to complete, may have business impact for many organizations. To reduce this, a different recovery procedure called Dial Tone Recovery might be preferable.

Here we will describe one of several possible dial tone recovery scenarios. This type of recovery will provide users with empty mailboxes from an empty database located on the same or a different server. Users will be able to send and receive emails while the database is restored from backup.

Dial tone recovery consists of the following steps:

Since the original database files are not available, once we replace the hard drive, we will try to mount the database from the Exchange Management Console or the Exchange Management Shell. The console will display the warning:

Clicking on Yes will mean that an empty database is to be created. When we mount this database, the users will be able to connect to it. However their mailboxes will be empty. The most important fact in this scenario is that they will be able to send and receive new emails.

The recovery is now completed using the process described in our previous article Exchange 2010 Mailbox Server Backup and Restore Part2, where we merge the current mailboxes with those located at the Recovery Database.

Recovering a Mailbox Server

In some scenarios, the mailbox server is lost due to a hardware failure, and should be replaced by a new one. In that case we should perform a procedure for recovering the mailbox server.

This procedure consists of:

1. In Active Directory Users and Computers, we should reset the computer account of the failed Exchange Server. Just right-click the computer and choose "Reset Account". We do this so as to later join a new machine to the domain, with the same name as the failed server. The failed server will never be in use anymore, but the new computer will have its name and will take over from Active Directory all Exchange settings and configuration of the failed server.

2. Next, we install an operating system with appropriate service pack and hot fixes on the new server.

3. The new server should have the same computer name as the previous one.

4. The new server should then be added to the domain.

5. We should install the Exchange Server software on the new machine in recovery mode using the command:
   Setup.com /m:recoverserver

   Important: Keep in mind that Exchange stores most of its configuration in Active Directory. Installing Exchange using the recoverserver switch, will load that configuration on the new Exchange Server.

Once we complete these steps, the Exchange Management Console will display the same configuration as it was on the previous server, with the exception that the databases will be shown as dismounted. In fact, the databases do not exist physically on the server and should be restored using Windows Server Backup.

At the end, we should restore the Mailbox Databases using one of the procedures described in this article, and mount them.

After we complete this procedure, users will be able to connect to their mailboxes and will be able to send and receive emails.

Conclusion

In this article you learned how to restore mailboxes, how to restore mailbox databases and how to restore an Exchange Mailbox Server role using the Windows Backup feature included in Windows Server 2008 and 2008 R2.

In each scenario there is some amount of service downtime while the restore procedure is completed. This depends on the backup/restore technologies used and of course on the type of failure. The downtime can be minimized using multiple technologies, such as redundant hardware and Database Availability Groups.

In one of our next articles, we will talk about Exchange Native Data Protection, where you will learn how to make your Exchange data available without even performing a backup.