Using the Remote Replication Premium Feature 95When you activate the Remote Replication premium feature on the storagearray, you create two replication repository virtual disks, one for each RAIDcontroller module in the storage array. An individual replication repositoryvirtual disk is not needed for each remote replication.When you create the replication repository virtual disks, you specify thelocation of the virtual disks. You can either use existing free capacity, or youcan create a disk group for the virtual disks from unconfigured capacity andthen specify the RAID level.Because of the critical nature of the data being stored, do not use RAID Level0 as the RAID level of replication repository virtual disks. The required size ofeach virtual disk is 128 MB, or 256 MB total for both replication repositoryvirtual disks of a dual-RAID controller module storage array. In previousversions of the Remote Replication premium feature, the replicationrepository virtual disks required less disk storage space and needed to beupgraded to use the maximum amount of replication relationships.Replication RelationshipsBefore you create a replication relationship, you must enable the RemoteReplication premium feature on both the primary storage array and thesecondary storage array. You must also create a secondary virtual disk on thesecondary site if one does not already exist. The secondary virtual disk mustbe a standard virtual disk of equal or greater capacity than the associatedprimary virtual disk.When secondary virtual disks are available, you can establish a replicationrelationship in the MD storage management software by identifying theprimary virtual disk and the storage array that contains the secondary virtualdisk.When you first create the replication relationship, a full synchronizationautomatically occurs, with data from the primary virtual disk copied in itsentirety to the secondary virtual disk.Data ReplicationThe RAID controller modules manage data replication between the primaryvirtual disk and the secondary virtual disk. This process is transparent to hostmachines and applications. This section describes how data is replicated
