In a scenario where the Exchange Server is beyond repair and a recovery process has to be started, then we can use Windows Server Backup to restore the entire volume to the original location and that will restore all Mailbox Databases inside of that volume, and that is what we are going to go over in the first section of this article.
However, in some cases, we may have only one mailbox database that requires restore, and if we restore the entire volume we will overwrite information from a healthy mailbox database, and that is where we should consider restoring just one Mailbox Database and we will cover that in the second section of this article.
Restoring all Mailbox Databases from the same volume using Windows Server Backup…
In this scenario, we are going to restore the Mailbox Databases to their original location. This type of recovery is often used when the only server that you have crashed, and you restored the Exchange Server using the /RecoverServer switch (we cover this process on the sixth article of this series) and now it is time to restore the Mailbox data that was being protected previously with Windows Server Backup.Let’s say that we have the administrator mailbox with two items on its Inbox, as shown in Figure 01, and then all of a sudden the Exchange Server crashed. Well, the first action is to perform the recovery of the server (covered on the article number 6 of this series), and then we need to restore the Exchange Mailbox Databases.
Figure 01
As soon as the server restarts from the recovery process, we will notice that all mailbox databases are dismounted (Figure 02), and at this point we should have all drive letters but without any mailbox database files on them. We can always check the properties of the mailbox databases to make sure that the path defined on the Mailbox Database object exists on the server.
Figure 02
Since we have been protecting our Exchange Server using Windows Server Backup (as shown in the seventh article of this series), we can open Windows Server Backup and then click on Recover… (Figure 03) and follow these steps.
Note:Since this server was just recovered, the Windows Server Backup may not have been installed, and if that is the case, we need to install the feature before continuing.
Figure 03
In the Getting Started page. Here we can select an existent backup location, by selecting A backup store on another location, then click Next.
In the Specify Location Type page. Click on Local Drives and click Next.
In the Select Backup Location page. Select the drive that was used to store the backup information, and click Next.
In the Select Server page. In case one or more servers exist on the location, they will be displayed on the list, select the Exchange server name from the list and click Next.
In the Select Backup Date page. Here is the key area for the restore, we have a calendar where every day that we had a backup is in bold letters, and after selecting the day, we can select the Time (in situations where we have more than one backup a day).
After selecting the day and hour of the previous backup to be restored, we can click on the link on the Recoverable Items folder and a new window with the volume (in our case M:) and two items will be listed. That weird number of the first two items is the GUID of the Mailbox Database that we can retrieve using the following cmdlet. The Windows Server Backup and the Exchange Management Shell used to retrieve the guid are shown in Figure 04.
Get-MailboxDatabase –Server <ServerName> | ft Name,EdbFilePath,LogFolderPath,Guid -AutoSize
Figure 04
In the Select Recovery Type page. Select Applications and click next. (Figure 05)
Figure 05
In the Select Application page. We will have Exchange listed under applications, just click on Next.
In the Specify Recovery Options page. Select Recover to original location (Figure 06) and the reason is that we do not have any data on the disks right now and we need to restore the Mailbox Database, click Next.
Figure 06
In the Confirmation page. A summary with all the items that will be recovered will be displayed, click on Recover (Figure 07). To start the process and that may take a while depending on the size of the Mailbox Databases that are being restored (I’m sorry, we are talking of Windows Server Backup, so in fact we are restoring the entire volume, thus all mailbox databases that we have in it).
Figure 07
The final page will be similar to figure 08, where we will see each item restore status, and how much information was transferred.
Figure 08
If we look back to the databases in Exchange Admin Center (EAC), we will notice that they are mounted (Figure 09) and the users have access to their information and all the information available is from the backup that we choose during the recover process.
Figure 09
Restoring a Single mailbox Database…
Now, we have a different situation we have our server with two Mailbox Databases residing on the same volume (M: drive) however just one database is corrupted and since we do not want to touch the databas that is healthy we cannot use the previous procedure to restore the information.We can check the databases information using Exchange Admin Center (EAC) where we can see that only DB01 is Dismounted however, DB02 is healthy (Figure 10).
Figure 10
In the Getting Started page. Select This Server (<ServerName>), click Next.
In the Select Backup Date page. Select a day, and then the time that you want to restore, and click Next.
In the Select Recovery Type page. Select Applications and click next.
In the Select Application page. We will have Exchange listed under applications, just click on Next.
In the Specify Recovery Options page. Select Recover to another location (Figure 11) and we are going to create a folder on the temporary drive (X: drive), and the name for that folder will be Restore, after defining the location click Next.
Figure 11
In the Confirmation page. Just click on Recover to start the process, which may take a couple of minutes/hours to finish depending on the size of the volume. In the final page of the wizard just click on Close.
In the folder that we defined as destination for the restored files we will have a subfolder for each mailbox database (the name of the folder will be based on the guid attribute of the database, which makes it easy to identify what we want to restore). Inside each main folder, we will have the volume and the directory structure where the mailbox database was protected.
We must look for the Exx.chk file (where XX is the Log Prefix of the Mailbox Database that we are trying to restore) and the DB01.edb is the mailbox database file (Figure 12), and we will use that information in a few moments.
Note:If the logs and database files are not in the same volume, we must restore them as a pair. Just restoring the database volume will not help, in this current situation the database and logs are on the same volume which makes things much easier.
Figure 12
In order to check if the database is in a healthy state we can use the command below, but first we need to be on the same location of the EDB file using either Exchange Management Shell or command (we should use cd FolderName to go deeper in the structure of directories).
Eseutil /mh <file.edb>
In Figure 13, we can see that the database is in Dirty Shutdown state and in this state, we cannot mount it.
Figure 13
We need to use the eseutil utility in recovery mode (/r) to bring the database to a clean shutdown state and we can do that by using the following syntax, the results of that command line is shown in Figure 14.
Eseutil /r <LogPrefix> /l <Path-Log-Files> /d <Path-Database-File>
Figure 14
Now, we can run the same eseutil /mh <database.edb> and the state will be clean shutdown, as shown in Figure 15.
Figure 15
In order to restore the database we can just place the EDB file in the original location on the Exchange Server (Figure 16). If there are files from the previous database, we can move them to a temporary location to be safe, but the goal is to keep just the brand new restored EDB file on that folder.
Note:If a folder does not allow removal, then we can stop the service Microsoft Exchange Search Host Controller and then try to remove that folder (related to the Search Service)
Figure 16
After cleaning up the folder and making sure that the EDB is in clean shutdown state, we can use Exchange Admin Center (EAC) to mount the database (Figure 17), a confirmation will be required. After that, the users will have access to their content, which was restored from the restore process that we have just completed.
Figure 17
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