easy points - match vdisk to windows disk?

[Trever Furnish]

Surely this is an FAQ and thus easy points for someone...hopefully? Haven't figured it out by googling yet though. :-(

How do I know for certain which vdisk goes with each Windows 2008 disk?

We have an EVA6400 and are presenting vdisks to Windows 2008 servers (among others). The win2k8 boxes are running Microsoft's built-in MPIO.

On the windows side the MPIO tab of the disk properties shows 8 paths, as expected, and I can see ctd numbers and a "lun ID", and the lun ID SEEMS to match up with the LUN ID used to present the vdisk from the eva, but of course those aren't guaranteed to be unique on the host. Perhaps the combo of ctd numbers AND lun ID is unique?

What would be really nice is if someone has a handy little script that can correlate all the way from the world wide lun name of the vdisk to the disk number inside windows storage management. That's all I'm really looking for -- a way to be 100% sure (quickly and easily) that a given windows disk is really a particular eva vdisk.

[Michael Leu]

As a unix/storage guy I really miss a easy way to get the WWID of a LUN on windows. All I found was this:

Powershell:
http://blogs.msdn.com/b/taylorb/archive/2010/06/30/getting-more-information-about-you-cluster-lun-s-part-2-of-3.aspx

C++ code:
http://blogs.msdn.com/b/adioltean/archive/2004/12/30/344588.aspx

[CLEB]

Look in the MPIO DSM Manager, there you can see what WWN maps to which Windows partition letter.

[Sheldon Smith]

And while you are in HP's MPIO DSM Manager, enable ALB on the LUNs so the host will use the paths to the vdisks' owning controller. Then set preferred controller on the virtual disks to balance the traffic.