Comment 22 for bug 1278529

Having the same error however I'm using dreamhost objects for s3. Ubuntu precise.

Main action: collection-status
================================================================================
duplicity 0.6.18 (February 29, 2012)
Args: /usr/bin/duplicity collection-status -v9 s3://objects.dreamhost.com/mybucket/
Linux mybrokenvps 3.1.9-vs2.3.2.5 #1 SMP Thu Jan 26 02:37:05 UTC 2012 x86_64 x86_64
/usr/bin/python 2.7.3 (default, Feb 27 2014, 19:58:35)
[GCC 4.6.3]
================================================================================
Releasing lockfile <lockfile.LinkFileLock instance at 0x2ba8f80>
Using temporary directory /tmp/duplicity-qdOTHd-tempdir
Backend error detail: Traceback (most recent call last):
  File "/usr/bin/duplicity", line 1432, in <module>
    with_tempdir(main)
  File "/usr/bin/duplicity", line 1426, in with_tempdir
    fn()
  File "/usr/bin/duplicity", line 1275, in main
    do_backup(action)
  File "/usr/bin/duplicity", line 1304, in do_backup
    sync_archive(decrypt)
  File "/usr/bin/duplicity", line 1037, in sync_archive
    remlist = globals.backend.list()
  File "/usr/lib/python2.7/dist-packages/duplicity/backends/_boto_single.py", line 260, in list
    raise BackendException("No connection to backend")
BackendException: No connection to backend

WORKAROUND:

Using the '--s3-unencrypted-connection'

I did manage to find a workaround. Using the '--s3-unencrypted-connection' option works and I'm able to connect/download/upload. This means there is an ssl issue here.

FIX:

install the latest version of: libssl1.0.0

After some comparing with a machine where it does work I found the the library: libssl1.0.0 was older then the one where it did work. After upgrading to the latest available version it worked. In my case it worked with version (1.0.1-4ubuntu5.12 & 1.0.1-4ubuntu5.13)

Hope this helps some of you.