View Full Version : AirDisk Time Machine Backup

12th July 2008, 01:06 PM
So, I've been using my 1TB external hard drive for time machine backups over USB. I've just hooked it up to my AirPort Extreme but time machine couldn't find it. So, under preferences I changed the backup disk to the AirDisk (the same external hard drive I was using before) and that worked fine. The only problem is it won't continue using the already created backup files on the disk, it wants to create a new backup folder. This will take forever.

So, is there anyway to tell Time Machine to continue using the backups it already created when the drive was hooked up via USB?


12th July 2008, 01:34 PM
Nope, cannot be done. It will create new TM backups in a sparse-image file from memory.

12th July 2008, 01:51 PM
Do the first backup over (gigabit?) ethernet if you can..

12th July 2008, 07:19 PM
As much as the idea is appealing, doing a Time Machine backup to an AirDisk is not recommended.

Time Machine support by the AEBS is an officially un-supported feature, and the reason why it is unsupported is that some USB bridge-chips used in external enclosures do not work as expected with Apple hardware. Time Machine requires a 100% stable connection; if the connection disappears even momentarily during the course of a backup write, and the Time Machine host does not receive the proprietry error-check-fail response (which is only present in Time Capsule and Mac OS X Server 10.5.2 or greater) then the archive becomes corrupt.

(Yes, Apple know about this. No, they have no intention of fixing it, and have also said that TM-capable AirDisk may disappear in a future firmware update for the AEBS.)

If you value your backups, stick to having your Time Machine drive plugged into the machine directly, or upgrade to a Time Capsule.