Along with a whole bunch of other improvements and new features, New-Migrationbatch is one of my favorite new additions to the Management Shell.
Prior, if you were moving mailboxes between mailbox servers in e.g. Exchange 2010, you had to use New-MoveRequest to start/request a mailbox move from one database/server to the other. If you had multiple mailboxes you wanted to move at once, you had several options:
Use Get-Mailbox and pipe the results along to New-Moverequest
Import a CSV-file and pipe the results along to New-Moverequest
Create an individual move request for each users
While these options are still valid in Exchange Server 2013, you now also have the ability to create a migration batch using the New-MigrationBatch cmdlet.
This cmdlet will allow you to submit new move requests for a batch of users between two Exchange servers, local or remote (other forest) and on-prem or in the cloud (on-boarding/off-boarding). If you have been performing migrations to Office 365, this cmdlet shouldn’t be new to you as it was already available there.
The nice thing about migration batches is that you can easily create them, without having to start or complete them immediately. Although with a little effort you could’ve also done this using New-Moverequest, it’s not only greatly simplified, the use of migraiton batches also gives you additional benefits like:
- Automatic Reporting/Notifications
Pre-staging of data
Just as in Exchange Server 2010, the switchover from one database to the other is performed during the “completion phase” of the move. During this process, the remainder of items that haven’t been copied from the source mailbox to the target mailbox before are copied over after which the user is redirected to his “new” mailbox on the target database. (for purpose of staying on track with this article, I’ve oversimplified the explanation of what happens during the “completion” phase)
Creating a migration batch
To create a migration batch, you’ll need to have a CSV-file that contains the email addresses of the mailboxes you are going to move. These can be any of the email addresses that are assigned to the mailbox. There is – to my knowledge – no requirement to use the user’s primary email address.
Also, the file should have a ‘heading’ called “EmailAddress”:
Next, open the Exchange Management Shell and run the following cmdlet:
[sourcecode language=”powershell”]New-MigrationBatch –Name <name> –CSVData ([System.IO.File]::ReadAllBytes(“<full path to file>”)) –Local –TargetDatabase <dbname>[/sourcecode]
Running this cmdlet will start a local mailbox move between two Exchange server in the same forest. However, it will not automatically start moving the mailboxes as we haven’t used the –Autostart parameter. Furthermore, the moves won’t be completed automatically either because the –AutoComplete parameter wasn’t used either.
Note It’s important that you specify the full path to where the csv-file is stored (e.g. C:\Files\Batch1.csv). Otherwise the cmdlet will fail because it will search for the file in the sytem32-folder by default.
Once the batch is created (and you didn’t use the –AutoStart parameter), you can launch the moves by running the following cmdlet:
[sourcecode language=”powershell”]Get-Migrationbatch | Start-MigrationBatch[/sourcecode]
Please note that if you have multiple migration batches, this cmdlet will start all of them.
Polling for the status of a migration
You can query the current status of a migration on a per-mailbox basis using the Get-MigrationUserStatistics cmdlet. The cmdlet will return the current status of the mailbox being moved and the amount of items that have been synced/skipped so far.
[sourcecode language=”powershell”]Get-MigrationUser | Get-MigrationUserStatistics[/sourcecode]
Note Alternatively, you can also use the –NotificationEmails parameter during the creation of the migration batch. This parameter will allow you to specify an admin’s email address to which a status report is automatically sent. If you don’t use this parameter, no report is created/sent.
Completing the migration
If you didn’t specify the –AutoComplete parameter while creating the migration batch, you will have to manually start the “completion phase”. This can easily be done using the Complete-MigrationBatch cmdlet.
[sourcecode language=”powershell”]Get-MigrationBatch | Complete-MigrationBatch[/sourcecode]
When you take a look at the migration statistics, you’ll see that the status will be “Completing”:
Once mailbox moves have been completed successfully, the status will change to “Completed”
As you can see, the New-Migrationbatch will certainly prove useful (e.g. if you want to pre-stage data without performing the actual switchover). Of course, there are other use cases as well: it’s the perfect companion to use for cross-forest moves and moves to/from Office 365 as it contains numerous parameters that can be used to make your life easier. For instance the Test-MigrationEndpoint cmdlet can be used to verify if the remote host (to/from which you are migrating) is available and working correctly. This is especially useful in remote mailbox moves (cross-forest) or between on-prem/cloud.
If you want to find out more about the cmdlet, go and have a look at the following page:
Alternatively, you could also run Get-Help Get-NewMigrationBatch –Online from the Exchange Management Shell which will take you to the same page!