In a previous entry I described a problem with Apple’s Backup utility that caused it to ignore most Quicken data file updates. I’m pleased to report that the current version of Backup, version 3, backs up Quicken data files correctly.

If you look on your backup volume to see what’s happening, you can see that, for incremental backups, a new backup archive is created for each backup. The first one is a full backup, and is of course as large as the data you are protecting; the incremental ones are smaller, being archives of only the changed files.

This differs from the Backup 2 approach, where a single backup archive was updated in an incremental fashion for each backup. One of the things I like about the new scheme is that this multi-file approach allows for the recovery of any given backup, like a revision control system. This allows you to survive cases where you did violence to your data on your own, not by hardware or software failure but by overwriting or deleting a file you hadn’t meant to. Backup 2, with its single archive, could only attempt to recover your most recent backup. The downside is that Backup 3 requires a bit more space on your backup volume, but this certainly seems worth it.

Most importantly, MacOS X packages (like the Quicken data files) are copied into the incremental backup archive in their entirety whenever any part of them changes. So it appears to be safe to use Backup 3 to protect those sorts of files now.