Logical Unit Number Mapping
This is the process by which the host operating system assigns a LUN value to a particular storage volume. LUN Mapping is typically used in cases where the higher level applications require specific LUN numbers for specific storage devices. When there are multiple paths between a SCSI initiator and SCSI target, multi-pathing software is used to properly map target volumes via both the paths. Storage controllers provide access control mechanisms (LUN Masking) that can control how initiators access target storage volumes.
At host, LUN mapping is performed by operating system software. If one wants to properly manage multiple paths to a storage volume from a host, then one needs to install a multi-pathing driver on the host. LUN mapping is also performed by virtualization software that is present in network virtualization boxes. These boxes perform mapping between virtual volumes that are exported to hosts and the physical volumes residing on the...