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coolsport00Flag for United States of America

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RDM Size

Hello all...looking for options here is all...something I may be overlooking.
I have a VM with Volumes associated with it; as far as virtual infrastructure goes, those Volumes are RDMs from a fibre channel EMC CX4 SAN. I want to add another RDM to the VM, but the problem is the LUN I want to map to (RDM) is 2.6TB. I didn't think RDM'd volumes mattered necessarily as far as the storage config max of 2TB goes, but it does it seems. Is there a way to get this to work with the size I'm wanting to have? My only thought for getting this to work (have a single volume on the VM) is to destroy the LUN I have now (at the moment, there's no data on the LUN), create 2 LUNs of 1.3TB, add them to the VM, and make them dynamic volumes so as to span them into 1 volume. Does anyone have any ideas how to overcome doing it like this?...in other words I want to be able to add 1 RDM (if possible) and be done with it.
I have ESX4 and the above mentioned SAN.

Thanks! :)
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Paul Solovyovsky
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Since this >2TB storage will only be used by a single VM, have you thought of split the large LUN to 2 smaller LUNs as you described above and extend one to the other one to create a larger volume. Mind you that there are pros and cons of doing this. Make sure you do  your home work.
Just food for thoughts.
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The thought came to mind, but not sure how to do an 'extent' as I've never done it before. If you have a doc/ref handy, that would be great; otherwise, I'll research it.

Thanks both.

~coolsport00
The pros of this solution is that you can have a single volume presented to your ESX host with larger than 2TB size, i believe you can have up to 32 extents if my memory serves me right :) but, the downfall of this solutions is not recommended if you have large number of VMs accessing this volumes because if you have scsi locks on your first LUN, all your extents will also be locked for any access. That's why this might be ok since only one VM is accessing this volume in your case.
Good luck mate!
Yes, 1 and only 1 VM will ever be accessing this LUN/volume, so if the con is with other VMs potentially needing access to the LUN, that will never be, so seems like no issue there. Any good documentation on creating extents "bb.."?

Thx.

~coolsport00
Here's a screenshot of step by step config:
Extend VMFS Datastore in VMware vShpere
http://blog.wilmsenit.nl/?p=630

Hope it helps coolsport00
Hmm...that references a datastore, which is not what I'm wanting. I need to make this LUN mapped to my VM via RDM. I want to keep my data on my SAN, not a part of a datastore within my vSphere infrastructure. So, I assume extents are out of the question then? :)

~c
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Hey "ryder"...good to see you back on here! :)

Yeah...thought so as I haven't found anything else stating otherwise.

~coolsport00
Thanks for the replies all. I'm gonna do this as I stated in my orig post.
yeah, i did some testing in the lab, and no luck :( can't find anything out there that can help do this at this point, hopefully maybe the next release? :)
Good luck coolsport00!
hey mr cool...nice to see you are still busy collecting points :p
Tryin to anyway - still learning lots from "paul..", "arun", "bb.." there above, and "jakethecatuk", as well as others. :)
If you have iSCSI capability to your SAN you can setup MS iSCSI initiator and have a GPT volume attached up to 12TB
I don't...just FC...thx "paul.." :)

Hey...are any of you going to VMworld here in the states? You are in the states already, aren't you "paul.."?
I just moved to London UK from Canada, so maybe gonna try VMWorld Europe Copenhagen this year in Oct :) Anyone might be there?
Ha..gosh, I wish! I don't think my Director will let me go to Europe for VMworld tho! :P
I'm in the US but I have a lot of projects coming up and being a consultant they don't pay me for not being onsite.  Just spent a week in Netapp NCDA training.

It's usually in Vegas, I try to make it at least once a year, if I can schedule during vmorld I'll see if I can go depending on schedule
I really wish I could go too but the cost to travel to US is too expensive, dont think my comp will send me there since I'm supporting Ausie clients :(
I actually haven't been yet.. I've gone to other conferences, but think I'll be able to go this year. I wish it was in Vegas this year. It's in San Fran...which isn't bad, but would rather it be in Vegas. Well..maybe someday we can all meet up at some conference and shoot the technological breeze :)
lol... gotta love Vegas!!! according to the previous location trend, they should go back to Vegas next year. Would be super awesome to meet up at a future vmworld though lol...