I have three remote Linux desktops running behind a router which I need to maintain from behind my router. It has worked perfectly with TeamViewer (TV) 10 until recently, when TV have tightened up their rules on the free version and they now require the most recent version (TV 14). Sadly TV 14 will not run on (K)Ubuntu 14.04 (Trusty), which has just reached end-of-life. Clearly I need to upgrade my 14.04, but there will be many upgrade problems on the way and I need a workaround for the time being.
What remote desktop options are there and how do navigate the routers without having to set up port forwarding for each separate machine:
Thanks in advance.