MSA1500: How to take backup of LUN's on second controller?

[Jaxx]

I have an MSA1500 with 2 controllers in active/active configuration, 2 SAN-switches, 2 HBA pr. server, FF MPIO for MSA, and one MSL6030-E1200 connected to SAN-switch nr.1. My problem is that I dont understand how to take backup of LUN's that are presented to servers through controller nr. 2.

The release notes for MSA firmware 7.0 states to disable load-balancing on the host side. That leaves me with failover on the HBA's on the servers. So far it's ok.
To distribute load on the controllers I would then have to manually present some LUN's on controller 2 and also set the preffered path on the HBA to the path that leads to Controller 2. But then I dont have access to the MSL library anymore wich is on SAN switch 1. To me it seems that the only option is to present all LUN's on controller 1, but then there is no point in having an active/active config either.

Any has any ideas how to do this?

[John Kufrovich]

Don't manually assign LUNs to controllers unless you know what you are doing. Your performance can suffer. You could set a preferred path at the hba and the MSA will move those LUNs to that path.

The OS doesn't know about the path to the data, it is MPIO's responsibility to figure everything out.

[Jaxx]

Hi. Thx for replying.

But if I understand you correctly that will not help or change my situation.
If I set preferred path on the servers and let the controllers balance the lun's automatically, the controllers will eventually put the LUN on the controller witch is connected to the preferred path?

Then I'm back to the same problem, that servers with preferred paths (on the HBA's) set to controller 2 cant see the backup library. And if I set the preferred path (on the HBA) to controller 1 then there will be no loadbalancing between the controllers, since all LUN's will eventually be automatically presented on controller 1!

Or am I thinking totally wrong here?

[Jaxx]

Ups, I think I'm thinking totally wrong here.
I thought that when setting preferred path on MPIO that kind of "disabled" the other HBA path. But of course it doesnt. This is path pr. LUN. Both paths is still active and I will see my library anyhow. I'll test it.
Thx.
If I have any more twisted ideas I'll get back to you. :-D

Jaxx