However this means you need to remember everytime you create a new child to enable the page file for that child.

While I haven’t tried this yet, I would imagine that if you have multiple hard drives, you could put the base on one and the differencing on another, and might possibly obtain a performance improvement over having a single image on one hard drive. Even if not that performant, it should still be a big improvement over having the base and differencing on the same platter.

To James: yes, it does get slower the more levels of differencing you have. Similarly, Hyper-V snapshots are slower when there are more levels (not necessarily more snapshots — with 20 snapshots, all from the same base, there’s only one “level” when running any of them (and 2 VHDs to look in); but with 20 snapshots, each taken from the preceding snapshot, then there would be 20 VHDs that the system may need to look in to find a file).

Cheers,
Ken

I’m creating virtual machines mostly so they can be moved around when we get new PCs.
They don’t get created and thrown away that often.

I seem to recall there is an issue with Undo Disks and differencing disks, but can’t recall exactly what it is. I’ll try and ask around tomorrow and see what I can come up with.

As far as I can tell, and let me stress I AM NOT A LAWYER so this is not legal advice, just what I can figure out, the only need for a license key is for the base machine you inherit from. From there on out no matter how many differencing machines you create technically you are running the original OS.

On question 2, No, from what I have read the base cannot be patched which is one of the drawbacks. If you patch it (or change it in any way) you break all the machines it descends to. It’s one of the few drawbacks to the way it works, any service packs, hotfixes, or patches have to be applied to the children.

Arcane

Two questions for you, 1. on each of the Differencing Disk, is there a need to require a Windows license key? Since the OS bits are not on the differencing disks, so may be not … ? 2. Can the Base Disk be patched? Say we need to apply a Service Pack or whatever on it after Differencing Disks been created? If we can patch the Base and it automatically applies to all Differencing Disks afterwards, then no need to patch each of every DD’s.

Thanks.