[slothrop]

I'm working on implementing a backup rotation with SD that looks like this:

1. current mirror (to a partition on an external Firewire drive, bootable)
2. last week (as a sparseimage - no need to boot this directly)
3. last month (also as a sparseimage)

This isn't hard; I can use SD to smart update from the (current) backup partition to the "last week" sparseimage, which is easy and fast.

I'd like to be able to do the same thing from the "last week" image to the "last month" image (much faster than copying the whole image file in the finder). But when I try to select an existing sparseimage file from the "copy" file picker in SD, they're all grayed out. Is it possible to clone a sparseimage to another sparseimage with smart update?

This isn't very high priority, since copying with the finder is an obvious workaround, but it would save maybe an hour of disk thrashing every time I do the "last week" -> "last month" rotation.

Am I missing something obvious? Is there a technical limitation on doing sparseimage-to-sparseimage smart updates?

Thanks,
Matt