HP-UX 11i v3 Native Multi-Pathing for Mass Storage (August 2012)

17
Last Open or Close state = ACTIVE
LUN path : lunpath13
Class = lunpath
Instance = 13
Hardware path = 0/4/1/0.0x500508b3009097f9.0x4014000000000000
SCSI transport protocol = fibre_channel
State = UNOPEN
Last Open or Close state = ACTIVE
LUN path : lunpath16
Class = lunpath
Instance = 16
Hardware path = 0/2/1/0.0x500508b3009097f1.0x4014000000000000
SCSI transport protocol = fibre_channel
State = UNOPEN
Last Open or Close state = ACTIVE
LUN path : lunpath22
Class = lunpath
Instance = 22
Hardware path = 0/4/1/0.0x500508b3009097f1.0x4014000000000000
SCSI transport protocol = fibre_channel
State = UNOPEN
Last Open or Close state = ACTIVE
The previous output shows the lunpath states as UNOPEN; the LUN is currently not open. Furthermore,
the last open or close state is ACTIVE; the LUN is available for I/O traffic.
Statistics
You can observe the effects of the distribution of the I/O load across lunpaths using I/O transfer
statistics. Using scsimgr, administrators can gather the following I/O transfer statistics on lunpath
and LUNs. The
sar command can also display I/O throughput on LUN and lunpaths (see the Native
multi-pathing: an example).
In the context of LUN multi-pathing, it is also very useful to be able to monitor the behavior of lunpaths
and LUN components. Using error related statistics such as I/O errors and open errors system
administrators can readily identify failing components and understand the cause of the failure. For
instance, the administrator can gather the following lunpath open failure statistics and I/O errors
statistics:
# scsimgr get_stat -H 0/4/1/0.0x500508b3009097f9.0x4014000000000000
STATISTICS FOR LUN path : 0/4/1/0.0x500508b3009097f9.0x4014000000000000
Generic Statistics:
…
Open failures due to inquiry failure = 0
Open failures due to insufficient inquiry data = 0
Open failures due to invalid peripheral qualifier= 0
EVPD page 83h inquiries = 2757
EVPD page 83h inquiry failures = 0
insufficient EVPD page 83h inquiry data = 0
Mismatches of peripheral qualifiers = 0
Page 83h ids not associated with the LUN = 0
Open failures due to no page 83h response = 0
Open failures due to page 83h code mismatches = 0
Open failures due page 83h id mismatches = 0
Open failures due to page 83h length mismatches = 0
Open failures due to page 83h content mismatches = 0
…
I/O transfer Statistics:
…
Check condition status = 43