Managing host groups involves understanding the host mappings to the hosts groups and host access to the LUNs.
To use the host group feature, first create the host group, then assign your hosts to the group. After the host group is created and the hosts are assigned to the group, you can map your LUNs to the host group. A host that is assigned to a host group is still available for mapping by way of the host or the host group to which the host is assigned.
When deleting a host group, remove the host members first. Ideally, you would delete an empty host group that contains no host memberships. Emptying a host group involves moving each host to another group or removing the host from the group. This action might affect the current host-to-LUN mapping. After moving a mapped host to another host group, you will receive a confirmation to unassociate the host from the host group.
The system displays the confirmation to unassociate a host from a host group when there are LUNs mapped to a group. You can decide how you want the system to process the residual mappings. You are presented with two options:
Allows you to copy all mappings for the deleted host group to the hosts that belong to the group. The hosts that belonged to the deleted host group retains access to any LUNs to which they had access while a member of their host group.
Allows you to remove all mappings for the deleted host group. The hosts that belonged to the deleted host group lose access to any LUNs to which they had access while a member of the host group. Choosing this option causes the message No Mappings to appear in the LUNs overview page if the LUN is not assigned to a host or host group. The Delete Mappings option does not affect any LUNs that are mapped to the host (and not to the host group).