We, sysadmins, love ntop. But it’s sometimes too much if we just want a quickie view on network usage, or checking which connection is currently hogging our network bandwidth.
So I came across iftop, a text app which is included in main repositories and gives an immediate view of the most used connection pairs. Great to use in any NAT box, routing machine, or even at home
Just apt/yum install it to get it working!