Dual Layer DVD+R = Fusion VM Backed Up

I picked up a stack of Sony DVD+R DL disks this morning in preparation for my first attempt at DL burning. The objective: Backing up my Fusion install of Windows XP onto two disks.

The XP vm is about 15 GB. I don’t back it up with Time Machine, but I have a separate volume on the Time Machine drive where a copy of the vm is kept. Now I can delete it if I feel the need. The way I use Windows doesn’t require updating the backup with something like SuperDuper. I’m just saving myself from ever enduring the install process by storing a copy.

Burning more than 8.5 GB ? Use Split.

First I dumped the vm folder into a .sparseimage file created with Disk Utility. Then I used the split command in Terminal to split the sparse image into two files. That was simple enough, apart from the annoying difference between GB and GiB.

The disks have 8.5 GB stamped on their tops. That’s the manufacturer’s way of making the capacity look bigger - using decimal notation instead of binary. OS X reported the blank disk as having 7.96GB free.

The disks burnt well, no coasters. If I ever need to restore the XP vm I can copy the files from my dvd+R dl disks and reconstitute them with the cat command. For two bucks I reclaimed 15 GB on my external drive. Not bad. That’s thirteen cents per GB compared with around twenty-five cents per GB on an external HDD.