Reconfiguring Storage MSA 30 MI

[Guillermo Rossney]

Hi everyone.
We have bought a new server and a new storage solution, and we are installing it.

We have five discs on the storage, all of them attached to a single bus.

Actually, our server has two scsi cards, but it seems that only one is being used with the storage, or at least the disk's hardware paths shows that:

COMPAQ BD1468A4C5 140014 Mb 0/4/1/0.4.0 SCSI Ultra320 A6961-6001
COMPAQ BD1468A4C5 140014 Mb 0/4/1/0.3.0 SCSI Ultra320 A6961-6001
COMPAQ BD14689BB9 140014 Mb 0/4/1/0.2.0 SCSI Ultra320 A6961-6001
COMPAQ BD14689BB9 140014 Mb 0/4/1/0.1.0 SCSI Ultra320 A6961-6001
COMPAQ BD14689BB9 140014 Mb 0/4/1/0.0.0 SCSI Ultra320 A6961-6001

and the I/O interfaces are:
ext_bus 0/3/1/0 mpt SCSI Ultra320 A6961-60011
ext_bus 0/3/1/1 mpt SCSI Ultra320 A6961-60011
ext_bus 0/4/1/0 mpt SCSI Ultra320 A6961-60011
ext_bus 0/4/1/1 mpt SCSI Ultra320 A6961-60011

As far as we know (that is not much at all), if we move some discs to the other bus on the storage, and all cables are properly connected between server and storage, the HW paths will change, begining with 0/3/1, and in that case we will have two simultaneous channels for disks I/O, avoiding possible I/O bottlenecks.

Is that correct??

Assuming that, it is possible to do that change without lose the information already passed to that disks??

Any help will be appreciated, thanks in advance.

Guillermo

[Torsten.]

Hi,

the MSA30 with the MI (multi initiator) module has 4 SCSI connectors and 2 internal busses.

One bus is the left half of the chassis connected to the SCSI connectors A1 and A2,

the other (right) half is connected to B1 and B2.

You may connect 2 HBAs in the (HP-UX) server to one bus (you must adjust the SCSI ID from 7 to 6 of one controller) or you can share the MSA between 2 servers.


So if you want to mirror the disks, you should install let's say 2 disks on each bus.

How did you set up the cabling?

[Guillermo Rossney]

Hi Torsten, thanks for your answer.

The cables are connected this way:

MSA 30: A1 <-> ext_bus 0/4/1/0
MSA 30: B1 <-> ext_bus 0/3/1/0

[Torsten.]

Please have a look at this thread, it is the same problem, more or less.

If you have questions, please come back.

http://forums1.itrc.hp.com/service/forums/questionanswer.do?threadId=1110862

[Guillermo Rossney]

Continued on another thread.