My cunning plan is to recover data using a replacement Mac if the current one karks it.
I usually encrypt the disk image that Time machine uses, and the encryption password is stored on the machine's keychain.
Does this mean I can't decrypt the image on a replacement machine (because keychain is on the now-dead machine)?
Corollary: I can only make unencrypted TiMachine backups for this purpose?
The password in the keychain is only used to facilitate mounting of the drive.
If there is no keychain record (either because it was never saved there, was lost, deleted, etc.) then the OS will simply prompt you for the drive's password in order to mount it.
Same thing in Time Machine's case - the keychain password will be used to auto-mount the drive for backups. When it comes to restoring the drive to a different device you'll be prompted for the drive's encryption key/password, then you're set.
So your solution just requires that you remember/save the password somewhere outside of your main boot drive (e.g. your brain, a post-it note on the fridge, in a safety deposit box.... wherever you prefer :)
The password in the keychain is only used to facilitate mounting of the drive.
If there is no keychain record (either because it was never saved there, was lost, deleted, etc.) then the OS will simply prompt you for the drive's password in order to mount it.
Same thing in Time Machine's case - the keychain password will be used to auto-mount the drive for backups. When it comes to restoring the drive to a different device you'll be prompted for the drive's encryption key/password, then you're set.
So your solution just requires that you remember/save the password somewhere outside of your main boot drive (e.g. your brain, a post-it note on the fridge, in a safety deposit box.... wherever you prefer :)
Using time machine to recover from image on another machine: encryption and keychain get in the way?
