LUN presented to host not usable?

Question

I have a new cx310c and I am testing our ERP application to see how it will run on a new drive configuration on the new SAN (we have a cx300 as well). I have a test box, Dell 6850 with a Qlogic 2340 hba, I zone it on the fiber just fine. create some raid groups, create some storage groups, drop the host into the group and 3 new LUNS, one 450Gb, one 100GB and one 400GB. The first two allowed me to initialize them just fine but the third one will not. I have removed it, unbound it and recreated the lun in various sizes. The drive in Windows disk manager shows as Unknown and unreadable. Since this is a test box only and this will be scrapped anyway I only put one hba into the test box and didn't load powerpath thinking since I only have one path it isn't needed anyway. That shouldn't effect the third drive I added to the box. The first two initialized just fine. Any suggestions. p.s. the box is 64 bit.

dynamox · Accepted Answer

this one HBA is only zoned to one SP ?

nandas · Answer

Did you zone the HBA to both SPA and SPB ports on the Fabric? What is the current ownership of these 3 LUNs?
It may the case, the first 2 LUNs are owned by one SP which is zoned to the server, but the 3rd LUN is owned by the other SP and the path to that SP is not available to your host. Can you please check the same.

Thanks,
Sandip

ovivier · Answer

In Windows Disk Manager, when you see a disk "Unknown" and "unreadable" generaly it is the famous LUNZ.
It means that there is no LUN with ID 0. See these IDs in the Storage Group -> "LUNs" and watch the latest column in the right.

For example if you add a LUN ID 0 and a LUN ID 1, and later remove LUN in ID 0, you will still see on the server the LUN ID 1 and you will alse see the LUNZ in ID 0 as "Unknown" and "unreadable".

Another idea : is the third LUN completed bound ? Check if it not transitioning.

JimKearns · Answer

Thanks guys! You were exactly right, the drive in question was owned by the other SP. Once you mentioned it, that made perfect sense. I guess since I don't normally set them up like this (one hba)and I did zone it only to the one SP. Great insight.... man I should have thought of that. Cudos to you!

nandas · Answer

It's our pleasure to be of any help and nice to see the issue is resolved.

"Dynamox" - you are so kind to me .. so don't you want to get the 10 points

. I am happy with 6 (Helpful) if you want to take 10 (Correct)

- no complaints

dynamox · Answer

Sandip deserves the full credit ..i just started pocking around, fishing for more info ..when he came up with the answer glad it's working for you Jim.

CLARiiON

LUN presented to host not usable?

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