In this configuration, cluster-aware Backup Exec is installed on the controlling node, failover occurs to designated nodes in the cluster, and tape devices are attached to a shared SCSI bus that is separate from any shared SCSI bus for disks.
Because each node creates a unique tape device name for the same device, if the drive is not serialized, this configuration requires you to create a device pool that includes the tape device name used by each node in order for jobs to run when failover occurs.
When failover occurs, a SCSI bus reset is issued. Therefore, tape devices and shared drives should not be connected to the same SCSI bus; each should be connected to separate SCSI buses.
More Information
Creating device pools for Microsoft Cluster Servers