topic Re: Two adapters on same scsi chain in Disk Enclosures

Two adapters on same scsi chain

Antonio_73 — Wed, 13 Jul 2005 02:13:05 GMT

Is there any way to attach two adapters to the same scsi chain within a Storageworks 4314R cabinet?
We would like to have two servers, one working and one sleeping, connected to same disks.
Obviously only the working server will mount disks.

Regards,
Tonino

Re: Two adapters on same scsi chain

Thayanidhi — Wed, 13 Jul 2005 06:11:14 GMT

Hi,
As long you make sure that only one server access the disks one time, you can connect so.
You must change the SCSI controller id from default (default is 7). Also check all the SCSI id in the bus so that there is no SCSI id clash.

Regds
TT

It's prefered to have id 6 which has next highest priority on the SCSI bus.

Re: Two adapters on same scsi chain

Antonio_73 — Wed, 13 Jul 2005 06:45:31 GMT

Hi TT,

the main problem is how to physically connect two different adapters on the same chain with a Storageworks 4314R.

Your explanation is clear, but the problem I have is on practical execution.

Thanks,

Tonino

Re: Two adapters on same scsi chain

Uwe Zessin — Wed, 13 Jul 2005 06:54:49 GMT

The M4314R enclosure has fixed termination, so you need to link from it to the next server. Connect it with a Y-cable or a "TRI-LINK". This server *MUST* have termination disabled!! From there, connect to the second server. Best is to disable termination on its adapter as well and do an external termination.

Honestly, I would forget about this adventure. Keep the 'sleeping' server disconnected. If the primary one stops working - just reconnect the M4314R to the 'sleepy' one and wake it up.

Re: Two adapters on same scsi chain

Antonio_73 — Wed, 13 Jul 2005 06:58:32 GMT

Thanks for the answer.
What about using the last generation of dual I/O modules? HP is very ambiguos describing them: it looks like you may see the same drives from two different adapters. Or not?
Ciao,
Tonino