we have two DS3400 behind a V7000.
When I publish LUNs to a created Host "V7000" on either of the two DS3400, I cannot change the preferred node for thes LUNs.
Other LUNs, published to "real hosts" like W2k8, clustered or not, and Linux are still changeable from controller A to B and back. LUNS mapped to the V7000 I cannot move from one controller to the other, regardless if they are actually on A or B - both are working but not to change.
So there is no redundancy in our SAN for any of our V7000-Pools containing drives from any DS3400, firmwareupgrades on any of the DS3400 are impossible a.s.o.
IBM Support is involved since a week, but helpless at this moment.
We checked zoning, settings on V7000 and DS3400 and they found nothing faulty.
3 questions they cold not answer but are in my mind:
1: In the IBM-Informationcenter there is one setting described, that nobody could explain or could tell, how to do that, what it could mean, on a DS3400:
"Perform the following steps for the worldwide node name (WWNN) option:
- Set the system so that both controllers have the same WWNN."
2. According to this I defined the "Host" V7000 on the DS3400 as ONE host with all 4 FC-Ports - would it be suggested to define TWO Hosts, one for each V7000-node and cluster them? Or is this the answer on question 1: One host with BOTH controllers?
3. I did this with a V3700, too. From the V3700 the V7000 reports 2 external controllers. From a DS3400 it reports always only one. I think this is "works as designed", isn´t it?
Any idea is appreciated - thanks - Chris