Obnam is currently using paramiko as the SFTP implementation. It is a bit more limited than the SFTP protocol is, and so some stuff that Obnam should be doing, such as restoring hardlinks across SFTP, are not possible. There may also be some bugs with regards to timestamp handling.

Possible fixes:

• patch paramiko to support more of SFTP
• switch to twisted's conch or libssh or http://pypi.python.org/pypi/ssh/ or python-ssh2

--liw