Nov 08, '07 07:30:00AM • Contributed by: Anonymous
Here's a tip, if you use .Mac with a locally-cached iDisk.
There are two problems with Time Machine and iDisk. First, while the iDisk .dmg file is backed up, you have no access to any folders within your iDisk through Time Machine. This is kind of unfortunate, as I keep my all my personal documents on an iDisk (locally cached at both ends) to keep my iMac and Macbook in sync.
Second, every time you make the slightest little change to your locally-cached iDisk, Time Machine has to copy the entire disk image again. The same would apply to disk images for virtual machines, for instance. In addition to making your hourly backup more time-consuming, this will quickly eat up free space on your backup disk. Since Time Machine for iDisk is already pretty useless, just exclude the local DMG of your iDisk from Time Machine backups. After all, all the files on it are already backed up on .Mac servers, and on your other computer.
To do this, open Time Machine's System Preferences panel, click the Options button, then click the plus sign to add a new excluded location. In the file dialog that appears, navigate to ~/Library » FileSync, and click the Exclude button. I'd also recommend excluding any other large disk images you might have -- you can just make manual backups of these. Otherwise, your Time Machine drive is going to fill up pretty fast.
Hopefully, a future update to Time Machine will have special provisions for these large, frequently-updated files, and possibly will provide an interface for iDisk backups. (One solution to the iDisk problem would be to not have the local cache of the iDisk be a disk image, but rather some hidden-away bundle.) In the meantime, save yourself a headache and exclude local iDisk images and other large files from Time Machine.
