HP-UX System Administrator's Guide: Routine Management Tasks HP-UX 11i v3 (B3921-90023, September 2010)

A new feature, the Storage Enclosure Framework feature, has been added to this release.
The Storage Enclosure Framework enables HP-UX to identify enclosures attached to
the system and to identify the LUNs, lunpaths, target paths, and target ports associated
with an enclosure. For more information about the Storage Enclosure Framework, see
scsimgr(1M)
For more information about the mass storage stack, see the Next Generation Mass Storage
Stack white paper.
HP-UX 11i v3 Device Special Files
HP-UX 11i v3 provides persistent DSFs (Device Special files) for mass storage devices.
A single persistent DSF is created for each LUN, not bound to the path to the device
as in prior HP-UX releases, but to the LUN’s Worldwide Identifier (WWID), a unique
and permanent identifier of the LUN. This makes the DSF persistent and agile, that is,
independent from the physical paths to the device. This also enables transparent
multi-pathing, meaning that any available path to the device can transparently be
selected to access it. An example of persistent DSF name is /dev/disk/disk13.
NOTE: Persistent DSFs will remain persistent for the life of a system, even after a
recovery. However, they are not persistent if you cold reinstall an HP-UX 11i v3 system.
HP-UX 11i v3 Hardware Paths
HP-UX 11i v3 provides a representation of hardware paths for mass storage devices,
referred to as a lunpath hardware path, which coexists with the legacy representation of
hardware paths already used in versions prior to HP-UX 11i v3.
The lunpath hardware path format enables the use of more targets and LUNs than are
permitted in the legacy addressing scheme. It is identical in format to a legacy hardware
path, up to the HBA, and represents the same path to the LUN. Beyond the HBA,
additional elements representing a transport-dependent target address (for instance,
a target port World-Wide Name for Fibre Channel or a port id for SCSI) and a 64-bit
SCSI LUN address, are printed in hexadecimal.
Note: the hardware path elements size has been increased from 8 bits to 64 bits to fit
these additional elements.
The lunpath hardware path format may be used to specify boot paths as explained
further in this section.
For more information about the format of hardware paths, see HP-UX System
Administrator's Guide: Overview.
Booting HP-UX on HP Integrity Servers: Details and Variations
HP-UX System Administrator’s Guide: Overview describes the basic sequence of events
that occurs when you turn on, reset, or reboot an HP Integrity Server. This section
36 Booting and Shutdown