HP P6000 Replication Solutions Manager User Guide (T3680-96089, October 2012)

Controller software features - remote replication
HP P6000 Replication Solutions Manager supports the remote replication features of the array
controller software listed below. For more information, see Table 6.3, Supported remote replication
features by controller software version, in the HP P6000 Enterprise Virtual Array Compatibility
Reference. See (page 288) for document location. For support of newer versions, visit the HP Storage
website.
Disk groups
Disk group is the term for a named pool of storage on a storage system in which virtual disks can
be created. See Online and near-online disk group categories.
IMPORTANT: Unless noted otherwise, the term disk group applies to storage system disk groups
and not to host volume disk groups that are under the control of a host OS or logical volume
manager. Storage system disk groups are managed through HP P6000 interfaces and not by
logical volume managers.
See also DR groups Maximum log disk size.
Remote data replication protocols
Remote replication can be configured with the following protocols.
HP FC Data Replication Protocol. This protocol uses Fibre Channel in-order delivery in which all
exchanges between the source and destination use the same path. Performance may be limited
because routing cannot utilize available alternate paths. A storage system that configured with this
protocol will only successfully create a DR group with another storage system that uses the same
protocol.
This protocol requires that fabric switches be configured for in-order delivery and Source
ID/Destination ID (SID/DID) routing. See the HP P6000 Continuous Access Implementation Guide
for specific settings.
CAUTION: Improper configuration of fabric switches can result in significant performance
degradation. HP FC Data Replication Protocol should not be used with a SAN configured for
exchange-based routing.
HP SCSI FC Compliant Data Replication Protocol. This protocol uses Fibre Channel exchange-based
routing in which all frames within a given exchange use the same path, but other exchanges can
use other paths. This allows for improved performance.
This protocol supports fabric switches that are configured for exchange-based routing. For more
information on data replication protocols, see the HP P6000 Continuous Access Implementation
Guide.
Remote replication tunnels
In HP P6000 Continuous Access remote replication configurations, controller software attaches
remote replication tunnels to the path between a controller host port on the source and destination
storage systems.
Although there can be several paths between source and destination controllers, there can only
be one tunnel connecting a source and destination controller (two tunnels between a given pair of
source and destination storage systems). Controllers optimize performance by automatically
changing the host ports (paths) that are used for the tunnels.
With some versions of controller software, you can set the priorities for host port selection, for
example to help load balance remote replication traffic. User requested priorities are targets; they
are not absolute settings. The controllers will make the actual host port assignments based on
real–time circumstances; for example, when a link, port or switch failure in the highest priority
238 Storage systems