Disks sharing same bus?

[William Pribble]

Could someone please tell me if the following two drives are sharing the same bus? Thanks

ext_bus 1 0/0/2/0 c720 CLAIMED INTERFACE SCSI C875 Ultra Wide Single-Ended
ext_bus 2 0/0/2/1 c720 CLAIMED INTERFACE SCSI C875 Ultra Wide Single-Ended

My primary root drive is on path 0/0/2/.0.6.0
My alternate root drive is on path 0/0/2/1.6.0

[yairg]

I think that you using the same bus

try iostat

[Jeff Schussele]

Hi Elaine,

They share the same system bus (0/0/2), but NOT the same SCSI bus (0/0/2/0 & 0/0/2/1). They have the same SCSI ID (6) so you'd have trouble if they were on the same SCSI bus.

Rgds,
Jeff

[Helen French]

They are defenitely NOT on the same SCSI bus. Both disks are connected to different SCSI controllers (especially when they have same SCSI ID -6).

[A. Clay Stephenson]

There are on different buses (and indeed they would have to be since they are both SCSI Target ID 6).

There is one possible "gotcha" and that is it is just possible that this is an array LUN and that both paths point to the same LUN -- one being the primary path and the other an alternate path to the same LUN. If you know that this is not the case then then they must be separate physical devices.

[Sanjay_6]

Hi,

My guess is that they are on different bus.

do ioscan -fnkC disk |more

Look and see if the disks are using the same controller, c1 or c2 or c3 or so on.

If they are same, then it is the same controller, otherwise they are on different controller.

Hope this helps.

Regds

[Jeff Schussele · Accepted solution]

Elaine,

BTW - those are not disks you listed. They are the SCSI HBAs (Host Bus Adapters) that disks, tapes, CD/DVDs, etc would attach to.

And I thought those looked familiar. That's an N-class or an rp7430/50/70 system - correct?
Each of those SCSI HBAs hosts one of the internal disks & that's about it.
The SCSI HBAs both live on the same PCI bus, but the other drive will remain active if one of the SCSI HBAs goes bad.

Generally tapes & DVDs/CDs hang off another SCSI bus - on most of mine it's 0/0/1/0

HTH,
Jeff

[William Pribble]

I know those are the HBAs. HP was in today and said that my disks are using the same bus. I thought I would see what some of the forum users thought. BY the way it is a N4000.

Thanks Everyone..