two independent HP9000 to one HASS A3312A jamaica disk array?

[Steve Post]

I have an HASS A3312A Jamaica disk array with mirror disk/ux.
It has 8, 8gig disks. In it.

It is currently plugged into one HP9000 K570, using two scsi controllers. One controller for the left 4 disks. One controller for the right 4 disks.

It is like this....
boxA:scsi1----d1-d2-d3-d4-terminator
boxA:scsi2----d5-d6-d7-d8-terminator

I am only using disks d1, and d2.

I would like to hook up a second K570, and assign 4 disks to it like so:

boxA:scsi1----d1-d2-d3-d4-terminator
boxB:scsi1----d5-d6-d7-d8-terminator

Question 1:
It this possible? Can boxA see boxB's disks? (I want them to NOT see each other).


Also, I have two scsi controllers on box A and box B. Can I basically make a loop of scsi for each box. Ie:

boxA:scsi1----d1-d2-d3-d4-boxA:scsi2
boxB:scsi1----d5-d6-d7-d8-boxB:scsi2

Question 2: is this possible?

Both boxes are running hpux11.0. But box B is going to need more room. I would really like to dedicate 2 disks for vg00 hpux11i for each box, then another 2 disks for vg01 data. i.e.

I would like d1 for boxA vg00, d2 for mirror.
d3 for boxA vg01, d4 for mirror.
I would like d5 for boxB vg00, d6 for mirror.
d7 for boxB vg01, and d8 for mirror.

Yep. That's what I would like to do. But I can't find any documentation.

any idea where I should turn?

steve

[Torsten. · Accepted solution]

Both sides of the jamaica are independend and can be connected with a cable.
There are two busses,each with 4 disks.
Of course you can the left 4 disks for one system and right 4 for another. sys a won't see sys b disk.

It's also possible to connect sys a - disk -sys b - but you have to configure one of the HBAs to ID 6.

[Steve Post]

Ok Thanks.

On this thread, in my second part scenario, I would have two scsi host-bus-adaptors hooked out of a k570: one cabled to the top of the 4 disks on the left side. And the second scsi adapter cabled to the bottom of the 4 disks on the left side.

If this is the case, I would need to change one of the two scsi adaptors on the box from 7 to 6?

An ioscan of it (for box A or box B) would look like.....

c720 8/0
disk 8/0.1.0 c4t1d0
disk 8/0.2.0 c4t2d0
disk 8/0.3.0 c4t3d0
disk 8/0.4.0 c4t4d0
ctl 8/0.7.0 c4t7d0

c720 8/4
disk 8/4.1.0 c5d1d0
disk 8/4.2.0 c5d2d0
disk 8/4.3.0 c5d3d0
disk 8/4.4.0 c5d4d0
ctl 8/0.6.0 c5d6d0<--change to 6 right?


On your other comment, on that closed thread, I didn't understand what you were trying to say. (but that's a different thread anyway). For me, I was warning that the word "terminator" made ME incorrectly believe I shouldn't terminate the scsi cable at the spot where it goes into the hp box.

[DCE]

Question 1:

Yes. As long as you keep the sides separate, i.e. do no cross connect them.

Question 2: is this possible?
Don't know for sure on a A3312, but it "should" work - PVLinks



I would like d1 for boxA vg00, d2 for mirror.
d3 for boxA vg01, d4 for mirror.
I would like d5 for boxB vg00, d6 for mirror.
d7 for boxB vg01, and d8 for mirror.

Sounds like a plan - be aware you have the mirror and primary on the same channel.

[Torsten.]

for information, the "closed thread" is here:

http://forums1.itrc.hp.com/service/forums/questionanswer.do?threadId=955048

you are right with the scsi IDs.
It's possible, it's a good solution but not perfect.

The jamaica has a single backplane. This is the single point of failure.

Better solution: 2 jamaicas. But it's OK. You can define an alternate path in the volume groups. You are safe, if one scsi controller fails.
You are not safe, if a disk block the bus, if a cable go bad, if the jamaica fails, ...

[Steve Post]

Yeah I know it's not perfect. Actually I hope to move off the boxes before I have to use the disks for anything other than simple file storage.