My favorite ssh client connection to monitor my mail server activity in real time is using GCM (Gnome Connection Manager).
GCM is a multiple tabbed ssh client connection manager for gtk+ environments.
Starting with version 1.2.0 it only supports python3 and GTK 3. So it should run fine on any modern desktop environment.
If you can't update to python/gtk 3 and only have python2/gtk2, then keep using GCM version v1.1.0 from https://kuthulu.com/gcm/.
Click the link below if you would like to install GCM package on your pc/laptop device for free.
Cliclk the link below to connect GCM to your mail server using secured shell connection ssh client.