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Just a short query: I have a Dell Md3200i setup to serve LUNs to my 2 physical hosts and I'm running vSphere/ESXi v5 with a number of VM's. Is it normal behavior for ALL VM's and LUN's to run off the one controller all the time? At the moment everything is running through Controller1.

I setup 2- 6 drive RAID10 arrays and wanted 1 array running via Controller0 and the other array via Controller1 to get a bit of load balancing going. But when I set 'Ownership' like that in the MD Manager it seems to migrate itself back to the one controller.

When I check the VM's MPIO modes in ESXi they all have 4 paths back to Controller1 as Active and 4 paths back to Controller0 as Standby.

I have played around pulling one controller out and it seems to all re-route itself to the other Controller. So it seems like its all via one controller at a time but just wanting to make sure I didn't screw something up in the setup ;)

Is this expected behavior??

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Hmmm, we have recently set up an MD3220i, out the box this worked fine, set one virtual disk to use one controller, second disk to use the second controller. Both have stayed put for several weeks now. Sounds to me like you may have an issue with one of your controllers? or perhaps an issue with the iSCSI paths from that controler to your hosts? – Daniel Kingdon Dec 4 '11 at 11:10
Yeah, I had some issues initially witht he MD3200i which needed a replacement controller....I'm just wondering if there is still somethign wrong with the MD3200i even though I now have a number of servers running OK off it. May have to get back onto Dell ...again.... – vlannoob Feb 1 '12 at 5:33

you can set up a controller as primary and as stdby, for every LUN. Since the MD3xxx is an LSI rebrand, it uses RDAC, and RDAC has half the paths in stadby, it's an active/passive path management system, unlike MPIO which is active/active

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The array seems to be configured for redundant paths: has built in. Unless you choose a daisy chain connectivity with more is the default behaviour.

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Cheers Jon. As per above, I have two arrays setup and was wanting one array to use Controller0 and the other Controller1. For some reason when I set this within a few hours BOTH arrays end up on one controller together. – vlannoob Dec 4 '11 at 4:45

I don't have the MD3200i, but I do have 4 MD3200's.. for the SAS controllers, you can set each virtual disk to use a different controller as primary.. You can't do that for the individual partitions you create inside the virtual disk.. You really want to split them, so they don't fight each other for writes.. (and same with the disks underneath)

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Thats what I was going for Brian. In the MD Manager software I tried to set each array to use a particular controller, and therefore each LUN I created in that array would get the same setting. Its sets OK....but within a few hours I get an 'Alert' in the MD software and I can see that the array is using the non-preferred controller. So both arrays end up on the same controller. – vlannoob Dec 4 '11 at 4:44

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