HP StorageWorks SAN Virtualization Services Platform Manager User Guide (5697-0454, May 2010)

11 Working with host groups
A host group contains multiple hosts. A host can only belong to one host group. Virtual disks that are
presented to a host group are automatically presented to all the hosts in the host group, in which
case, the virtual disk is given the same LUN for all hosts in the group. Individual hosts in a host group
can also be presented virtual disks independent of the host group, in which case, the LUNs used for
presenting those virtual disks is taken from the LUN range of the host group to which the host belongs.
By default, the LUN range of a host group is the intersection of the LUN ranges for all of the hosts in
the group. The LUN range can also be defined manually. If a host group does not actually contain
any hosts, the LUN range of the host group is the largest set of LUNs possible, unless manually defined
otherwise.
Only hosts meeting the following conditions can be added to a host group. The host:
• Is a user defined host (UDH)
• Is not already a member of another host group
• Does not have one or more virtual disks presented to it which are already presented to the intended
host group
• Is connected to all the DPMs or DPM groups that expose the virtual disks assigned to the intended
host group
• Does not reduce the LUN range of the host group to an empty set. For example, a host with a LUN
range that does not overlap with the LUN range of the intended host group would result in an
empty LUN range
• Has a LUN range which can contain all LUNs currently presented to the intended host group
You can:
• View the host groups list (view all the host groups exposed to the local SVSP domain)
• View host group information (view detailed information related to each host group in the tabs
area below the host groups list)
• Create host groups
• Add a host to an existing host group
• Remove a host from a host group
• Change the LUN range of a host group
• Rename a host group
• Delete a host group
Viewing the host groups list
The host group list displays all the host groups exposed to the local SVSP domain.
To view the host groups list:
1. In the navigation tree, expand the Entities node.
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