Dell PowerVault MD3420 - Manual (Page 94)

• The local storage array serves as the primary side of the Remote Replication group, while the remote
storage array serves as the secondary side of the Remote Replication group.
• At the virtual disk level, all virtual disks added to the Remote Replication group on the local storage
array serve as the primary role in the Remote Replication configuration. Virtual disks added to the
group on the remote storage array serve the secondary role.
Once you have selected virtual disks at both the remote and local storage array that you want to pair in a
replication relationship, adding them to a replication group actually begins the replication
synchronization process.
For more detailed information on the role of Remote Replication groups, see the Administrator's Guide.
Previous Users Of Remote Replication (Legacy) Premium
Feature
If you have upgraded (or plan to upgrade) your RAID controller firmware version to a level that supports
both legacy and non-legacy Remote Replication, any legacy replication configurations you have
previously set up will be unaffected, and will continue to function normally.
Remote Replication Requirements And Restrictions
To use the standard Remote Replication premium feature, you must have:
• Two storage arrays with write access and both these storage arrays must have sufficient space to
replicate data between them.
• Each storage must have a dual-controller Fibre Channel or iSCSI configuration (single-controller
configurations are not supported).
• Fibre Channel Connection Requirements — You must attach dedicated remote replication ports to a
Fibre Channel fabric environment. In addition, these ports must support the Name Service.
• You can use a fabric configuration that is dedicated solely to the remote replication ports on each
RAID controller module. In this case, host systems can connect to the storage arrays using fabric.
• Fibre Channel Arbitrated Loop (FC-AL), or point-to-point configurations, are not supported for array-
to-array communications.
• Maximum distance between the local site and remote site is 10 km (6.2 miles), using single-mode fibre
Gigabit interface converters (GBICs) and optical long-wave GBICs.
• iSCSI connection considerations:
– iSCSI does not require dedicated ports for replication data traffic
– iSCSI array-to-array communication must use a host-connected port (not the Ethernet
management port).
– The first port that successfully establishes an iSCSI connection is used for all subsequent
communication with that remote storage array. If that connection subsequently fails, a new
session is attempted using any available ports.
Primary And Secondary Virtual Disks
Before you create any replication relationships, virtual disks must exist at both the primary site and the
secondary site. The virtual disk that resides on the local storage array is the primary virtual disk. Similarly,
the virtual disk that resides on the remote storage array is the secondary virtual disk. If neither the primary
virtual disk nor the secondary virtual disk exist, you must create these virtual disks. Keep these guidelines
in mind when you create the secondary virtual disk:
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