By default, the Commvault software automatically discovers new availability groups in SQL server environment and configures availability group clients and instances, so that the availability groups are backed up.
Existing Clients
If automatic discovery is enabled, the software identifies physical SQL instances, and configures the new instances (that are not yet configured). If automatic discovery is not enabled, the software identifies existing SQL instances, and does not configure new instances.
For each SQL instance, the software checks whether the instance is the primary replica for any availability groups. If there are availability groups for the instance, the software checks if there is any existing availability group client configured for the instance. If there are no availability group pseudoclients for the instance, the software again checks whether the availability group databases are part of any subclient content of the physical SQL instance. If the availability group databases are not part of any subclient content, the software creates a new availability group client and configures the availability group instance.
If there is an existing availability group client, the software adds an availability group instance to the same availability group pseudoclient.
New Installations
By default, automatic discovery of applications is enabled when you install the agent on a new SQL client. When automatic discovery is enabled, the software automatically identifies and configures the SQL physical instances. For each instance, the software identifies the availability groups for which the instance is a primary replica, and then creates an availability group client with instances for each availability group.
On both existing and new installations, when you back up the default subclient of a physical SQL instance, the process for automatic discovery of databases discovers the availability group databases as well, and checks whether the databases are part of any existing availability group instances. If the databases are part of an already configured availability group instance, the backup operation does not add the databases to the subclient content. If the availability group databases are already part of the subclient content, they are automatically excluded from the backup.