How to do Lun reset and target reset on HPUX?

LUN reset - Resets the specified LUN by clearing any SCSI reservation on the LUN and making the LUN available to all servers again. The reset does not affect any of the other LUNs on the device. If another LUN on the device is reserved, it remains reserved.

Target reset - Resets the entire target. The reset clears any SCSI reservations on all the LUNs associated with that target and makes the LUNs available to all servers again.


Get the 3PAR raw disk number to which “LUN / Target reset” operations needs to be done:

 $ scsimgr lun_map

 LUN PATH INFORMATION FOR LUN : /dev/rdisk/disk449

 Total number of LUN paths     = 2
World Wide Identifier(WWID)    = 0x60002ac0000000000000011f00000098

 LUN path : lunpath59
Class                         = lunpath
Instance                      = 59
Hardware path                 = 0/0/4/0/0/0/0.0x21110002ac000098.0x400f000000000000
SCSI transport protocol       = fibre_channel
State                         = UNOPEN
Last Open or Close state      = ACTIVE

 LUN path : lunpath74
Class                         = lunpath
Instance                      = 74
Hardware path                 = 0/0/6/0/0/0/0/4/0/0/1.0x20120002ac000098.0x400f000000000000
SCSI transport protocol       = fibre_channel
State                         = UNOPEN
Last Open or Close state      = ACTIVE

LUN Reset:
$ scsimgr lun_reset -D /dev/rdisk/disk449
Do you really want to continue? (y/[n])? y
scsimgr: lun_reset operation succeeded
Target Reset:
$ scsimgr warm_bdr -D /dev/rdisk/disk449
Do you really want to continue? (y/[n])? y
scsimgr: warm_bdr operation succeeded


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