HP StorageWorks SAN Virtualization Services Platform Administrator Guide (5697-0934, May 2011)

Figure 16 Zoning between VSMs and first quad of a DPM pair
VSM-storage zoning
A VSM-Storage back-end zone is used to give the VSM access to the ports of the back-end storage
device to manage the storage being virtualized by SVSP, and facilitate data mover functions
involving the “soft path” such as mirroring, local snapshots, and remote replication. A back-end
path between the VSM and the storage device consists of a single port on the VSM and a storage
device port. In this type of zone, the VSM acts in the initiator role. Each VSM port is zoned to all
storage device ports on a given fabric. A VSM-Storage zone may contain a single VSM port and
multiple storage device ports. The VSM server is limited on the total number of access paths that
can be exposed to back-end LUNs. The restriction is set according to the capabilities of the OS
that runs the VSM (Windows 2008). However, there is a limitation on the number of back-end
LUNs that can be presented to the VSMs. See the product release notes for the maximum number
of back-end LUNs supported by HP SVSP. Each zone has a single VSM back-end initiator port and
multiple storage device target ports.
Figure 17 (page 41) illustrates zoning between VSMs and a dual, dual-port controller back-end
storage device. This can be extended for storage devices with more ports by adding them to the
existing zones. Paths between the storage device target ports and VSM initiator ports are color
coordinated to represent the different zones to which they belong within the red and blue fabrics.
Figure 17 Zoning between VSMs and two dual-port back-end controllers
VSM-VSM zoning
The VSM-VSM zone allows the VSMs in an HP SVSP configuration to communicate with each other
over the SAN in order to determine VSM connectivity state and manage failover behavior between
the VSMs. This special purpose zone is not classified as a front-end or back-end zone since it does
not involve any storage devices or hosts. In this type of zone, a VSM is not strictly classified as a
VSM-storage zoning 41