Mappings
Mapping is the process of controlling which hosts or host clusters have access to specific volumes within the system.
Each mapping associates a volume with a host or host cluster and provides a way for all WWPNs and iSCSI names in the host or host cluster to access the volume. You can map a volume to multiple hosts or host clusters. Mappings can either be shared or private. Shared mappings are volume mappings that are shared among all the hosts that are in a host cluster. When a host cluster is created, any common volume mappings become shared among all the hosts within the host cluster. If a mapping is not common, it remains a private mapping for that host only. Private mappings are mappings that are associated with an individual host. To view whether mappings are either private or shared mappings, select . The Mapping view displays all private mappings by default. From the view menu, select either Shared Mappings to view shared mappings for hosts or All Host Mappings to display all configured private and shared mappings. When a mapping is created, multiple paths might exist across the SAN fabric or Ethernet network from the hosts or host cluster to the nodes that are presenting the volume. Without a multipathing device driver, most operating systems present each path to a volume as a separate storage device. The multipathing software manages the many paths that are available to the volume and presents a single storage device to the operating system. If there are multiple paths, the system requires that the multipathing software run on the host or host cluster.