USB HDD to Guest... But what if Parallels isn't running?

Hi all,

I have an OS X Server host and an OS X Server guest. I have a Drobo hard drive array I want to connect to the guest.

I need to know how Parallels handles this - and, if it handles it poorly, a workaround.

My issue is this:

When restarted, Parallels isn't running so the host gets ahold of the Drobo (I think).

Later, Parallels starts and grabs the device - disconnecting it from the host (causing potential data loss and maybe confuses Drobo) and connecting it to the guest.

What I need is to somehow make the host never ever ever ever connect to the Drobo. Does Parallels already do this? Or does anybody know a workaround?

OR!

Can I have Parallels take over a partition and give it to the guest as a removable disk (without suffering much/any of a performance hit) (in case the disk loses power while running, I don't want Parallels to freak out).

Any suggestions would be greatly appreciated!


Note: to those who gawked at the performance hit statement above: I know I know I know. Some virtual adaptations give 1-2% overhead, which is fine - and others, like some of VMWare's network virtualization, adds a 200% overhead! That's what I don't want.