978 - ESE: How to back up and restore Exchange mailbox databases

Microsoft Exchange mailbox databases are backed up using Virtual Shadow Copy (VSS) technology which is able to read files typically locked by an application – such as databases. 

Active and passive databases

The replicated databases in Database Availability Group (DAG) will be indicated as “passive” in the backup selection tree. For standalone Exchange servers, all databases are indicated as “active”.

To view, just hover the mouse pointer over the Mailbox node to distinguish active mailbox databases from passive ones.

Online and offline databases

Mailbox databases can appear as “Offline” in the backup selection tree for different reasons, such as a stopped Exchange Windows service or if the database has been dismounted. When offline databases are included in the backup selection, they will be skipped during the backup process. The result is also reflected in the backup log. However, if the Server node is included, the skipped database will be backed up if it is online at the next backup. 

Tip: 

• If Full System Backup has been enabled, you can exclude databases to prevent those from being backed up.
• While in the Backup Selection tab, press F5 to refresh your view of the backup selection.