Exchange Server 2010 includes a new feature that can automatically load balance the provisioning of new mailboxes across multiple mailbox databases. Although the Exchange administrator can still specify a mailbox database if they want to, it is no longer mandatory and the Exchange server can make the decision as to where to provision the new mailbox instead.
This is useful in many different scenarios such as:
- Simplifies the help desk role of creating new mailboxes by removing the need for help desk staff to choose an appropriate mailbox database
- During bulk mailbox provisioning or mailbox migrations the mailboxes are automatically spread over all available mailbox databases
Despite the benefits there are also situations in which the Exchange administrator would not want mailboxes automatically provisioned on a particular database. For example a mailbox database that is configured with a very large mailbox storage quota for VIP users should be excluded, or a new mailbox database that is still in the process of being configured for use should be excluded.
To exclude a specific Exchange Server 2010 mailbox database from automatic provisioning use the following command in the Exchange Management Shell.
[PS] C:\>Set-MailboxDatabase -Identity "Mailbox Database 04" -IsExcludedFromProvisioning $true
To re-enable the mailbox database for automatic provisioning set the value back to $false.
[PS] C:\>Set-MailboxDatabase -Identity "Mailbox Database 04" -IsExcludedFromProvisioning $false