In the some installations of SCDW, on the not very stable networks, the native pyton ssh-backend paramiko, which is used in the duplicity by default, showing very low productivity and in some circumstances causes the hanging of a process of copying backup pieces to the remote storage.

The problem was solved by reverting backend back to pexpect, which is working via OS scp|sftp commands. We made a small fix to intercept the OS exit code to achieve the usability as in paramiko.