Comment 16 for bug 1652410

>> You apparently performed a full backup on 2016-11-29 at 01:52 UTC,
>> did everything work fine during this backup? Was it successful ?
> Don't think so

Don't think so either, because your full backup on that date is only one volume long and that volume is 120 bytes long:

  ls -l /home/david/Dropbox/Backups
  [...]
  ... 120 Nov 28 17:52 duplicity-full.20161129T015237Z.vol1.difftar.gz
  [...]

FYI duplicity makes backups into sets of normally 25 MB volumes.

And then there's your first incremental backup on Dec 1 which doesn't look good since there are only volumes 2, 7, 15, 16, 23, 41, 49 of that backup set in your backup repository. Where are all the other ones? Did Dropbox eat them? And the normally-accompanying signatures and manifest files are nowhere to be found either.

I don't know if Déjà-Dup can recover from this situation and finish the partial incremental backup set but I wouldn't even lose time trying to be honest. I've always found the easiest way to recover from a severely failed backup is to delete the failed part (everything in your case) and start again. For good measure you can also delete the backup's cache directory:

  rm -r /home/david/Dropbox/Backups
  rm -r /home/david/.cache/deja-dup/f00ff76508010e2a830dd26b1d39db42

When you try again, you may want to test backing up a small subset of your documents instead of your whole user directory. That way you'll know quickly if it works or fails again. If it works, you can delete this test backup and start again with the whole thing.