Recovering Large Parallels VMs from OS X Time Machine

I've had a large-scale OS X Time Machine backup system running for a while.

Recently I accidentally logged off (rather than shut down) a Parallels VM for which I hand not written down the password, er, well, I wrote down the password but not what it was for.

So I figured I'd restore the Time Machine backup for the .pvm file (Parallels Virtual Machine) from the day before (I hadn't used it for several weeks) and I figured I'd be OK.

The first issue is that Time Machine takes about 30 to 40 minutes to restore a 25Gb virtual machine.

Unfortunately during that time the machine is basically running flat out in some kernel process so that you can do virtually nothing else.  This can be further aggravated by having Carbonite (which I also use) and/or Time Machine running backups.

Its best to turn these two off before starting anything like this.

Once the file is fully restored to disk by Time Machine I figured I'd just double click it and have it work.

Boy, was I wrong...

The first problem you will encounter (I am on Lion 10.7.5 running Parallels 7.0.15107 Revision 796624; September 3, 2012) is a dialog that tells you either the virtual machine is corrupt (The virtual machine cannot be used because its files are corrupted) to which you can only reply OK or one that tells you about reusing or creating a new MAC address for the restored copy.

If you see the corruption dialog OK it and then quite Parallels.

Apparently you have to move the file from one directory to another (I moved it to the Desktop).

This should get you past the corruption dialog - though I cannot find any reason for this.

Next you need to restart the VM.

This time you should get the MAC reuse dialog.

You have two choices.  Choosing the "Use Existing" path means nothing but failure.  Somehow Parallels remembers which VM uses which MAC address and they CANNOT be shared.

Choosing "Create New" should just make the VM believe that everything is the same save for the MAC address (if you have code or apps using the previous MAC address they will break).

However, after this things should be OK.

I fooled around for this for quite a while to make sure that it worked reliably (being upset that Time Machine backup did not work out-of-the-box).

The only real thing you need out of the .pvm file is the .HDD file buried inside the .pvm (its down two levels).  

You can use the "Parallels Mounter.app" to do this.

I cannot find it on my disk but it shows up when you use the "Secondary Click" option on the track pad to open up the "Open With..." dialog.

The disk mounter doesn't say anything at all if the disk is okay - no message appears and at best a brief progress bar flashes on the screen.   However, if you look on the Finder panel you'll see the drives a mounted Mac drives.

You can use this to move files on and off the Parallels drives.