About using NetBackup to protect SQL Server availability groups
NetBackup for SQL Server supports backups and restores of SQL Server Always On and read-scale availability groups. For information on supported versions and environments, see the Application/Database Agent Compatibility List.
Note the following limitations for backups of availability groups:
NetBackup does not support the following types of backups for availability databases:
Snapshot backups of filegroups or files
Instant Recovery backups
VMware backups
(Legacy policies) A grouped snapshot backup that includes databases in more than one availability group or both availability and standard databases
(Intelligent Policies) A grouped snapshot backup
Backups of non-readable secondary replicas
NetBackup can only back up databases in a replica when you allow user connections for the replica.
If a secondary replica is the preferred replica and it is non-readable, the backup fails. If a secondary replica is not the preferred replica, NetBackup skips the backup of that replica.
SQL Server does not support the following types of backups on a secondary replica:
Full backups
If a full backup takes place on a secondary replica, NetBackup converts the full backup to a copy-only backup.
Differential backups
Backups of this type result in a failed backup.
Copy-only transaction log backups
Backups of this type result in a failed backup.