A storage unit group allows you to configure multiple storage units which act as a single destination for backup jobs. The order in which storage units are used within a group depends on the storage unit selection option: prioritized, round robin, failover,media server load balancing.
Prioritized : Prioritized storage unit groups choose the first storage unit in the list that is not busy with other jobs, down (physically unavailable), or out of tape media (in the case of tape libraries). It then fills that storage unit with active jobs, and then moves on to the next available storage unit in the list. If all storage units are busy, any subsequent jobs will queue, and wait for the next available storage unit in the group.
Round Robin: Round robin storage unit groups choose the least recently used storage unit in the list that is available.
Failover : A failover storage unit group chooses the first storage unit in the list that is not down or out of media. All other jobs will queue waiting for this storage unit, even if it is busy. If the storage unit ever goes down (or runs out of media), then the jobs will fail over to the next available storage unit in the group.
media server load balancing: Choose the best available media server based on a ranking system.
