Aug 032016
 

I recently upgraded my primary laptop from Ubuntu 14.04 to 16.04 and suddenly discovered that when I ssh into some of my other boxes all the colors are gone!

As it turns out, a few of the boxes I manage are running older OS versions that became confused when they saw my terminal was xterm-256color instead of just xterm-color.

Since it took me a while to get to the bottom of this I thought I’d share the answer to make things easier on the next few who stumble into the spider web. First: Don’t Panic! — always good advice, unless you’re 9 and then you’ll hear that “Sometimes, fear is the appropriate response…” but I digress.

So, what happened is that my new box is using a terminal type that isn’t recognized by some of the older boxes. When they see xterm-256color and don’t recognize it they run to safety and presume color isn’t allowed.

To solve this, simply set the TERM environment variable to the older xterm-color prior to launching ssh and that will be passed on to the target host.

At the command line:

TERM=xterm-color ssh yourself@host.example.com

If you’re telling KeePass how to do a URL Override for ssh then use the following encantation:

cmd://gnome-terminal --title={URL} -x /bin/bash -c 'TERM=xterm-color ssh {USERNAME}@{URL:RMVSCM}'

The colors come back and everything is happy again.

Oh, and one more thing before I forget. If you’re like me and sometimes have to wait a long time for commands to finish because you’re dealing with, say, hundreds of gigabytes of data if not terabytes, then you might find your ssh sessions time out while you’re waiting and that might be ++undesirable.

To fix that, here’s another little tweak that you might add to your .ssh/config file and then forget you ever did it… so this blog post might help you remember.

Host *
    ServerAliveInterval 120

That will save you some frustration 😉