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Graham HirstFlag for United Kingdom of Great Britain and Northern Ireland

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"Virtual Disk not on preferred path due to AVT/RDAC failover" on MD3000i Storage Array

We had our MD3000i connected to an ESXi 4.1 host, which was exclusively used by a VM on it which was our file server.  After a recent reboot, this file server went loopy, so we have to rebuild it!

I rebuilt it on another ESXi 5.0 host and at first it looked to work ok and on the face of it, it is working ok, but the Modular Disk Storage Manager is saying that Array is non optimal.

Further investigation shows that the virtual disks configured with preferred controller 1 are all residing on controller 0!  If I manually change them back to 1, they change back to 0.

Nothing suggests a hardware fault at this stage, but in the error logs it refers to a AVT/RDAC failover.  The full error states:

Date/Time: 11/06/13 14:41:50
Sequence number: 10818
Event type: 4011
Description: Virtual Disk not on preferred path due to AVT/RDAC failover
Event specific codes: 0/0/0
Event category: Error
Component type: RAID Controller Module
Component location: RAID Controller Module in slot 0
Logged by: RAID Controller Module in slot 0

I would call Dell, but our support has just ran out and I'm cant rely on the company renewing it in a hurry, so any tips would be appreciated.
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Seaton007
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There should be an option to balance them or fail them back over to the other path.

Here is something else to check as well:
http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1009414
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ASKER

There is an option to 'Redistribute Virtual Disks', but that just puts the disks on their preferred path, which I've already done manually.

Is it possible that an ISCSI Initiator Config issue could be the culprit?
do you have multiple paths, and are you using any additional software supplied by Dell for path mangement?
Dells multi path driver has been installed as part of the Management software, but I'm not sure that the ISCSI Initiator is configured appropriately to take advantage of it.

I can ping all 4 of the Controller IP addresses from the host.  If I disable the NIC connected to controller 1 (that one that one take any virtual disks, its still pings them all.  However, disabling the NIC linked to controller 0 causing the shares to fall over.

I've attached the target tab of the ISCSI initiator as its not saving the Enable Multi Path option.
SnipImage.JPG
Just to clarify, the MD 3000i isn't presenting storage to the ESXI hosts as Data Stores.  Instead, its configured with virtual switches, that are assigned as additional NICs to the file server, which in turn uses the Microsoft ISCSI initiator to gain access to the assigned virtual disks.
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Graham Hirst
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I found the solution myself.... Ok, I got assistance from a Dell Technician, but don't tell anyone.