HP StorageWorks Device Mapper Multipath Enablement Kit for HP StorageWorks Disk Arrays installation and reference guide (AA-RW8RE-TE, June 2009)

"HP”
"HSV210"
group_by_prio
"/sbin/scsi_id -g -u -s /block/%n"
tur
"round-robin 0"
"/sbin/mpath_prio_alua /dev/%n"
uniform
immediate
"0"
18
100
vendor
product
path_grouping_policy
getuid_callout
path_checker
path_selector
prio_callout
rr_weight
failback
hardware_handler
no_path_retry
rr_min_io
}
device
…….{
for targets from other storage controllers…...
}
}
For example, in a typical configuration, a Linux host with a dual port HBA is connected to an EVA
8000 through two switches. In this case, if all the paths are available, the host has eight I/O paths
for any LUN presented from the EVA 8000. The multipath.conf file enables the host to view the
multipath map, as follows:
mpath85 (3600508b4001072a100039000277a0000) dm-2 HP,HSV210
[size=1.0GB][features=1 queue_if_no_path][hwhandler=0][rw]
\_ round-robin 0 [prio=240][active]
\_ 57:0:0:19 sdb 8:16 [active][ready]
\_ 56:0:0:19 sda 8:0 [active][ready]
\_ 64:0:0:19 sdf 8:80 [active][ready]
\_ 65:0:0:19 sdi 8:128 [active][ready]
\_ 66:0:0:19 sdg 8:96 [active][ready]
\_ 67:0:0:19 sdh 8:112 [active][ready]
\_ 80:0:0:19 sdac 65:192 [active][ready]
\_ 81:0:0:19 sdae 65:224 [active][ready]
mpath86 (3600508b4001072a10003900027800000) dm-3 HP,HSV210
[size=1.0G][features=1 queue_if_no_path][hwhandler=0][rw]
\_ round-robin 0 [prio=200][active]
\_ 57:0:0:20 sdc 8:32 [active][ready]
\_ 64:0:0:20 sdk 8:160 [active][ready]
\_ 56:0:0:20 sdj 8:144 [active][ready]
\_ 65:0:0:20 sdt 65:48 [active][ready]
\_ round-robin 0 [prio=40][enabled]
\_ 66:0:0:20 sdr 65:16 [active][ready]
\_ 67:0:0:20 sdu 65:64 [active][ready]
\_ 80:0:0:20 sdv 66:0 [active][ready]
\_ 81:0:0:20 sdw 66:16 [active][ready]
Path grouping
The information in the multipath map is presented by grouping the paths for a LUN with unique
identifiers, such as UID/WWN. The size, features, and the corresponding hwhandlers are
displayed following the unique LUN identifier.
Device Mapper Multipath Enablement Kit for HP StorageWorks Disk Arrays installation and reference
guide 19