Can VMs share the same vmdks?

[JonRoderick]

We have some zVM users (IBM mainframe virtualisation) who are able to configure their VMs so that each VM accesses the same read-only data disk. They make changes to a read-write copy of this disk, make it read only again then make it available to all the VMs they want to access the disk when they're ready.

Does anyone know if this is possible in VI 3?

I've done a quick test with W2k3 and if I create a small data disk on one then try and host it on another VM at the same time, I get the error:

'Failed to power on blahblahpathtodisk'.

I'm guessing this isn't going to work but would appreciate feedback.

[VirtualNoitall]

Hello,

The premise is the same as it is in the physical world: unless you are using clustering software on windows you should not share a disk; virtual or physical.

Hope that helps!

[JonRoderick]

Thanks

any ideas why it seems to be common practice on the zVM platform?

[JonRoderick]

Sorry, I forgot to say...the VMs involved will be SLES 9/10 VMs, not Windows - my brief testing was on Windows (as it was easiest to hand).

[VirtualNoitall]

I am sure there are a couple of reasons:

1)maturity of the virtualization platform

2)maturity of the OS\filesystem

3)???

I don't spend a lot of time in the linux space but you might find there are options there.