HP Fibre Channel Host Bus Adapters manual Interpreting Lunpath Hardware Paths HP-UX 11i

Interpreting Lunpath Hardware Paths (HP-UX 11i v3)

Lunpath hardware paths are a new representation of hardware paths introduced on HP-UX 11i v3, as part of the new agile representation of mass storage devices. For more details, see the Next Generation Mass Storage Stack HP-UX 11i v3 white paper at http://docs.hp.com/en/netsys.html#Storage%20Area%20Management .

This section describes how to interpret address elements in lunpath hardware paths. It also shows how to map between the legacy hardware path and lunpath hardware path formats.

Components of Lunpath Hardware Paths

The lunpath hardware path has three parts:

1.The HBA path is composed of a series of bus-nexus addresses, separated by a slash (/). It is identical to the HBA portion of a legacy hardware path.

2.The target address is transport-specific. With Fibre Channel, it is a port identifier. When printed by I/O commands like ioscan, the target address is separated from the HBA path by a period (.) and is printed in hexadecimal notation.

3.The LUN address is a SCSI 64-bit LUN indentifier, built from the address method and the LUN number. When printed by I/O commands, it is separated from the target address by a period (.) and is printed in hexadecimal notation.

The following table provides four examples:

Table 1-4

Lunpath Hardware path	HBA	Target address	LUN address
	path
0/5/1/	0/5/1/0	0x50060e8004276e12	0x4000000000000000
0.0x50060e8004276e12.0x4000000000000000
0/4/1/	0/4/1/0	0x500805f300083899	0x4010000000000000
0.0x500805f300083899.0x4010000000000000

Fibre Channel

The target address for a Fibre Channel device is the target port’s worldwide port name (WWPN). The fcmsutil command with the get remote option displays the WWPN as the Target Port World Wide Name. In this example, the WWPN is 0x500805f300083899:

# fcmsutil /dev/td0 get remote all

Target N_Port_id is = 0x010700

Target state = DVS_READY

Symbolic Name =

Port Type = N_PORT

SLER Capable (supports Retry & TRID) = NO

Target Port World Wide Name = 0x500805f300083899

Target Node World Wide Name = 0x500805f300083890

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