Duplicity backup fails with Python exception

[Sébastien Pierre]

When running a backup though SSH using Ubuntu's new integrated back-up, I got the following exception traceback:

Traceback (most recent call last):
  File "/usr/bin/duplicity", line 1359, in <module>
    with_tempdir(main)
  File "/usr/bin/duplicity", line 1342, in with_tempdir
    fn()
  File "/usr/bin/duplicity", line 1222, in main
    globals.archive_dir).set_values()
  File "/usr/lib/python2.7/dist-packages/duplicity/collections.py", line 684, in set_values
    self.get_backup_chains(partials + backend_filename_list)
  File "/usr/lib/python2.7/dist-packages/duplicity/collections.py", line 807, in get_backup_chains
    map(add_to_sets, filename_list)
  File "/usr/lib/python2.7/dist-packages/duplicity/collections.py", line 797, in add_to_sets
    if set.add_filename(filename):
  File "/usr/lib/python2.7/dist-packages/duplicity/collections.py", line 94, in add_filename
    (self.volume_name_dict, filename)
AssertionError: ({32: 'duplicity-full.20111018T212826Z.vol32.difftar.gz', 8: 'duplicity-full.20111018T212826Z.vol8.difftar.gpg', 10: 'duplicity-full.20111018T212826Z.vol10.difftar.gz', 12: 'duplicity-full.20111018T212826Z.vol12.difftar.gz', 20: 'duplicity-full.20111018T212826Z.vol20.difftar.gz', 21: 'duplicity-full.20111018T212826Z.vol21.difftar.gz', 23: 'duplicity-full.20111018T212826Z.vol23.difftar.gz', 24: 'duplicity-full.20111018T212826Z.vol24.difftar.gz', 25: 'duplicity-full.20111018T212826Z.vol25.difftar.gz', 28: 'duplicity-full.20111018T212826Z.vol28.difftar.gz'}, 'duplicity-full.20111018T212826Z.vol8.difftar.gz')

ProblemType: Bug
DistroRelease: Ubuntu 11.10
Package: duplicity 0.6.15-0ubuntu2
ProcVersionSignature: Ubuntu 3.0.0-12.20-generic 3.0.4
Uname: Linux 3.0.0-12-generic x86_64
ApportVersion: 1.23-0ubuntu3
Architecture: amd64
Date: Wed Oct 19 15:48:30 2011
EcryptfsInUse: Yes
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Release amd64 (20111012)
SourcePackage: duplicity
UpgradeStatus: No upgrade log present (probably fresh install)

[Michael Terry (mterry)]

This is more likely a fault of deja-dup, moving to that package.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.