For Release 5.2.1, the switch can support up to two SME clusters. The following prerequisites must be met for supporting multiple clusters. If these prerequisites are not met data loss can occur.
• For SME disks, the SME cluster must be set as disk capable.
• SME Tape and SME Disk cannot co-exist in the same SME cluster. Use different clusters for SME Disk and SME Tape.
• Multiple SME clusters can be supported on the same MDS chassis with the following requirements :
– SME tape cluster node is on one Cisco MSM18/4 switching module.
– SME disk cluster node is on another Cisco MSM 18/4 switching module.
– For the SSN-16, SME Tape and Disk belong to different crypto nodes and belong to different clusters.
• Do not use the same target ports in different clusters.
• The same disk cannot be part of more than one SME cluster otherwise data loss occurs.
• Do not add the same SME interfaces in two different clusters.
From MDS Release 5.2(6), SME Disk can write a signature to the media to identify the disk as a crypto disk. These SME clusters are called signature clusters. Nonsignature clusters are SME Disks that do not write a signature on the media to identify crypto on the disk.