Anyway to identify virtual disk from within windows

No, Windows doesn't name "disks", it enumerates them - Disk 0, Disk 1, etc.  You can change the names of "drives" (volumes), but not "disks".

This will probably work if each "disk" contains a single volume:  Say Disk 0 is your OS (C:), Disk 1 is your Exchange database (E:), and Disk 2 is for your logs (L:).  You can change the names of those drives to look something like this:

 

However, the "disks" are still labeled "Disk 0", etc.:

This would help you keep them straight when working with Windows.  What exactly are you trying to do?

As ever thank you for your reply:emotion-2:

I have inherited a system of

C: 273GB ; D; 3.4TB ;E: 3.4TB ;F  3.4TB

In omsa I can see four virtual disks. The first Virtual disk is  comprised of two dsks in a mirror. This is (of course) the C: drive.

However there are then three identical Virtual Disks comprised of four disks each.

As an example one of the three Virtual Disks is comprised of 1.2tb SAS disks in slots 0 to 3. Just for reference I would like to know which disk this actually is, is it D:, E: or F.

For instance if OMSA lerts me that the disk in  slot 6 is  reporting imminent failure I I may wish to do an emergency backup of it, but I would need to know which disk needs backing up

Is there a way to look at the info on the F: drive and be able to link it to a particular Virtual Disk?

Disk Management will show you which "disk" contains which volumes/drive letters, then you can name them appropriately, if you want - you could even name the D: drive something like "VD01" or "MUSIC-VD01".  That would help you visually and easily know which volume belonged to which RAID array.  Otherwise, Windows has NO knowledge of the individual disks that make up the array.  Both OS and OMSA are needed to determine which VD's contain which data.

For instance if OMSA lerts me that the disk in  slot 6 is  reporting imminent failure I I may wish to do an emergency backup of it, but I would need to know which disk needs backing up

Now, when talking about individual disks that make up an array, it is not possible from the OS/file system level to create a backup of one of those member disks.  If running a redundant array (anything but RAID 0), there is also no need to create a backup of an individual disk's contents, so there is no way to do this from the hardware's perspective; you simply remove the disk and replace it with another (or even rebuild the same disk if it is offline but healthy) then rebuild it to match the data in the array.  If OMSA alerts you that disk 6 is pred fail, you don't create a backup of that disk, you simply replace it with a healthy disk; you should always have a good backup of the entire contents of an array (not individual disks in the array), regardless of disk/array health (don't wait for failure/pred fail).

I was able to use "omreport storage vdisk" to get the relevant info.

It listed all of the vdisks, and one attribute it had was "device", this value referenced the windows disk number.

Using this information I was able to match up   the vdisk name and the OS disk name. I edited the values so they matched.