This problem has been discovered by me and also another user, so it does not seem to be related to either of our own configurations. I That said, I am SSH’ing to the machine from a Mac, he is using another Linux machine.
When we SSH into an Ubuntu 14.04 machine, we notice that pressing the tab key logs us of the SSH session. Meaning, the session just drops and we have to start all over. As a result, tab completion does not work.