HP MSA 1040 HP MSA 1040 SMU Reference Guide (762784-001, March 2014) - Page 129

Replicating a volume If the system is licensed to use remote replication, you can create a replication set that uses the selected volume as the primary volume, and to immediately start or schedule replication. The primary volume can be a standard volume or a master volume. To create a replication set you must select a secondary system and a secondary vdisk or volume. The secondary system can be the local system, or a remote system added by using the Add Remote System panel. When using the SMU it is recommended to select a secondary vdisk and let the secondary volume be created automatically, instead of selecting an existing secondary volume. For a secondary (replication-prepared) volume to be available for selection, it must be exactly the same size in blocks as the primary volume, and that is difficult to ensure, especially with maximum-size volumes. You can select the local system if you intend to create the replication set on the local system and then physically move the secondary vdisk's disks (or enclosure) to a remote system. Otherwise, select a remote system for which you've already added a management object on the local system. Local replication is allowed only if the primary and secondary volumes are in vdisks owned by different controllers. TIP: A best practice is to schedule no more than three volumes to start replicating at the same time, and for those replications to recur no less than 60 minutes apart. If you schedule more replications to start at the same time, or schedule replications to start more frequently, some scheduled replications may not have time to complete. IMPORTANT: Before starting this procedure, if you intend to use CHAP to authenticate iSCSI login requests between the local system and a remote system, do the following: • Create a one-way CHAP record on each system. On the local system, the CHAP record must refer to the node name of the remote system. On the remote system, the CHAP record must refer to the node name of the local system. Both records must use the same secret. (Mutual CHAP is not used between storage systems. CHAP records' mutual fields can be set but are not used.) To create a CHAP record, see "Configuring CHAP" (page 76). • After the CHAP records are created, enable CHAP on the primary system, the secondary system, or both. To enable CHAP, see "Changing host interface settings" (page 46). If both records don't exist or don't use the same secret, replication-set creation will fail. NOTE: If replication requests are sent to a secondary system whose temporary replication license has expired, the requests are queued but are not processed, and the secondary system reports event 472. If this condition occurs, check for this event in the event log, event-notification emails, and SNMP traps. To continue using replication, purchase a permanent replication license. IMPORTANT: To replicate between an HP P2000 G3 MSA system and an HP MSA 1040 SAN system, the secondary volume must be exactly the same size as the primary volume. To ensure the size is exactly the same when creating the secondary volume manually, use the CLI as described in documentation for the replicate volume command. To create a replication set and optionally start or schedule replication 1. In the Configuration View panel, right-click a volume and select Provisioning > Replicate Volume. 2. In the main panel, set the destination options: • Secondary System. Select a storage system to replicate the volume to. • Secondary Volume. Select either an existing vdisk in which to create the secondary volume, or an existing replication-prepared volume to be the secondary volume. For an explanation of the criteria that determines which vdisks are listed for selection, see "Criteria for selecting a vdisk to contain a secondary volume" (page 124). Replicating a volume 129