Adding backup selections to an Exchange policy with Instant Recovery
You can include each Exchange database in one backup policy. Or you can choose to include a database in more than one policy. In the latter case, ensure that enough snapshot volumes exist to satisfy the value for each policy that contains the database.
When you configure an Exchange snapshot backup policy, the only valid directives are: Microsoft Exchange Database Availability Groups:\ or Microsoft Information Store:\ (a database can be appended) .
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Configuring an Exchange snapshot policy with Instant Recovery