HP StorageWorks Network Storage Router M2402 V1.0 User Guide (March 2004)

219Network Storage Router M2402 User Guide
C
Addressing Methods and
Table Structures
Fibre Channel (FC) and SCSI systems use different methods of addressing
devices. The router has a method of translating device IDs so each SCSI device is
mapped to the appropriate Fibre Channel LUN. The SCSI buses establish the bus
connections between devices. Targets on a SCSI bus may internally address
LUNs. The addressing of a specific SCSI device is represented by the
BUS:TARGET:LUN triplet.
When a FC Initiator initializes on a loop, the host must first determine what
devices exist on the loop. Device discovery is performed and an FCP target device
list is built. Each device is queried for FCP LUNs (the LUNs are the actual
devices that the operating system will address.) The addressing used is the SCC
Logical Unit Addressing and Peripheral Device Addressing method, shown in
Table 18 through Table 23. First level addressing is supported, so only the first
two bits of the 8 bit FCP LUN are used.
Table 18: Addressing Sequence
Bit/Byte 7
6 5 4
3
2 1 0
N Address Method Address Method Specific
N+1 Address Method Specific
Table 19: Address Method Definitions
Code Description
00 Peripheral Device Addressing Method
01 Volume Set Addressing Method
10 Logical Unit Addressing Method
11 Reserved