ioscan - understanding /dev/rscsi

[brian_31]

# ioscan -fnC ctl
Class I H/W Path Driver S/W State H/W Type Description
=========================================================================
ctl 0 0/0/3/0.0.7.0 sctl CLAIMED DEVICE Initiator
/dev/rscsi/c0t7d0
ctl 1 0/0/3/0.1.7.0 sctl CLAIMED DEVICE Initiator
/dev/rscsi/c1t7d0
ctl 2 0/1/1/0.7.0 sctl CLAIMED DEVICE Initiator
/dev/rscsi/c2t7d0
ctl 3 0/1/1/1.7.0 sctl CLAIMED DEVICE Initiator
/dev/rscsi/c3t7d0

ctl 40 0/5/2/0.97.6.255.1.3.0 sctl CLAIMED DEVICE HITACHI DF600F
/dev/rscsi/c13t3d0
# ioscan -fnC ext_bus
Class I H/W Path Driver S/W State H/W Type Description
==========================================================================
ext_bus 0 0/0/3/0.0 side CLAIMED INTERFACE IDE Primary Channel
ext_bus 1 0/0/3/0.1 side CLAIMED INTERFACE IDE Secondary Channel
ext_bus 2 0/1/1/0 c8xx CLAIMED INTERFACE SCSI C1010 Ultra160 Wide LVD A6829-60101
ext_bus 3 0/1/1/1 c8xx CLAIMED INTERFACE SCSI C1010 Ultra160 Wide LVD A6829-60101
ext_bus 15 0/4/1/0.97.68.19.0 fcparray CLAIMED INTERFACE FCP Array Interface
ext_bus 12 0/5/2/0.97.6.19.0 fcparray CLAIMED INTERFACE FCP Array Interface
ext_bus 13 0/5/2/0.97.6.255.1 fcpdev CLAIMED INTERFACE FCP Device Interface

# ioscan -fnC fc
Class I H/W Path Driver S/W State H/W Type Description
=================================================================
fc 2 0/4/1/0 td CLAIMED INTERFACE HP Tachyon XL2 Fibre Channel Mass Storage Adapter
/dev/td2
fc 1 0/5/2/0 td CLAIMED INTERFACE HP Tachyon XL2 Fibre Channel Mass Storage Adapter
/dev/td1

As you can above the fc path (0/4/1) cannot see altenate paths..what is the /dev/scsi device i see for 0/5/2 path from ioscan -fnC ctl (first output) that i cannot see for the
0/4/1/0 path? Can someone explain? how couls i miss that for the fc card (/dev/td2). the storage have the checked the zoning and they say it is clean.

Thanks

Brian

[Sandman!]

What you're seeing are not alternate paths but instead two different modes of addressing i.e. PDA (peripheral device addressing) and VSA (volume set addressing).

Run command below to determine if you can see alternate paths to your disks:

# ioscan -funC disk

the output of the above command should show dual paths to each of the storage LUNs, one thru 0/4/1/0 and the other thru 0/5/2/0.

~hope it helps