使用 Ubuntu 14.04 一小段时间。备份开始失败并返回此消息：
Traceback (most recent call last):
File "/usr/bin/duplicity", line 1494, in <module>
with_tempdir(main)
File "/usr/bin/duplicity", line 1488, in with_tempdir
fn()
File "/usr/bin/duplicity", line 1337, in main
do_backup(action)
File "/usr/bin/duplicity", line 1370, in do_backup
globals.archive_dir).set_values()
File "/usr/lib/python2.7/dist-packages/duplicity/collections.py", line 697, in set_values
self.get_backup_chains(partials + backend_filename_list)
File "/usr/lib/python2.7/dist-packages/duplicity/collections.py", line 819, in get_backup_chains
map(add_to_sets, filename_list)
File "/usr/lib/python2.7/dist-packages/duplicity/collections.py", line 809, in add_to_sets
if set.add_filename(filename):
File "/usr/lib/python2.7/dist-packages/duplicity/collections.py", line 100, in add_filename
(self.volume_name_dict, filename)
AssertionError: ({1: 'duplicity-inc.20140615T154649Z.to.20140616T205256Z.vol1.difftar.gz', 2: 'duplicity-inc.20140615T154649Z.to.20140616T205256Z.vol2.difftar.gz', 3: 'duplicity-inc.20140615T154649Z.to.20140616T205256Z.vol3.difftar'}, 'duplicity-inc.20140615T154649Z.to.20140616T205256Z.vol3.difftar.gz')
请给点建议？