In his Blog, Duncan Davidson described in detail the process of fully restoring his Mac from a Time Machine archive. The procedure involves the Mac OS X Leopard install disc and the selection of the dated archive to revert to. Mr. Davidson reported that the process passed the "Trust, but Verify" challenge with flying colors.

"Most of Apple’s marketing around Time Machine focuses on it’s ability to go back in time and pick out individual files that were deleted or lost sometime in the past. It’s only mentioned as a side thought that you can also use it to fully restore your hard drive in case of a crash. Restoring an entire disk, however, is the acid test of any backup system," Mr. Davidson wrote.

From Leopard Install Disc, Utilities Menu

Mr. Davidson published screen shots all along the way that show what one can expect when doing this kind of total system restore. In addition, he pointed out that the restore process does have some wrinkles that should be noted and that, by virtue of the way it works, the process is rather slow.

"In the morning, my system was fully restored," the author reported. "After rebooting, everything was right where I left it. Well, that’s not entirely true. Not quite everything was there. Time Machine doesnit back up data that can be reconstructed, such as caches and indexes. This means that Spotlight will have to rebuild its index and won’t be immediately available. It also means that when you launch Mail, it will think it’s the first time it’s been launched and will go through a “Welcome to Mail” process where it imports all of the mail messages that are on your system. It’s not downloading things from your IMAP server, just recreating its database."

There were some other small gotchas, according to Mr. Davidson: "Another thing I saw was that iTunes needed to be reauthorized. I guess the data needed for iTunes authorization doesnit get slurped up by Time Machine. Interestingly enough, however, is that I didnit need to reauthorize Adobe Creative Suite. That was nice, as Iive already used both my authorizations—one on my desktop and one on my laptop—and wasnit looking forward to calling Adobe to ask them to reset things."

Mr. Davidson expressed his confidence in the Time Machine backup process. "In short, Time Machine passed the iTrust, but Verifyi challenge with flying colors. I’m pretty happy about that as it means that I can recommend that my friends and family..." he wrote. However, he also wisely advised that one should also keep a copy of all data offsite.

"Then again, if you’re currently not backing up at all, having even a single Time Machine backup volume is a massive improvement," he concluded.