HP Surestore Disk Array 12h - And FC60 Advanced User's Manual page 209

The port value will always be 255 when using PDA. The loop address, Fibre Channel Host
ID of the disk array controller module (two address possible, one for controller module A
and one for module B), is encoded in the Bus and Target segments of the hardware path.
For example, in the hardware path shown in Figure 80, the Bus value of 1 and Target value
of 2 result in a loop ID of 18:
BUS TARGET LOOP ID
0 0 0 1 0 0 1 0 = 18
Volume Set Addressing
Volume set addressing (VSA) is used to address disk array LUNs. A disk array LUN can be
identified in the ioscan output as an entry with a driver type of sdisk and a description of
HP A5277A. The LUN number is encoded in the Volume Number segments of the hardware
path.
Figure 81 illustrates the interpretation of the fields in the hardware path when using VSA.
Volume Set Addressing (VSA) Hardware Path
8/12.8.0.6.0.1.3
Volume Number bits 0 - 2 (LUN number 0 - 7)
Volume Number bits 3 - 6 (virtual SCSI bus 0 - 3)
Volume Number bits 7 - 13 (always 0 for the FC60)
Loop ID of controller module
Area (0 = point-to-point or private loop)
Protocol Type (8 = mass storage)
Adapter
Bus Converter
Figure 81
Volume Set Addressing Hardware Path
Verifying Disk Array Connection
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