being a dictator syadmin: finding bandwidth usage for each host

Yesterdays post, revolve around blocking sites. One of the reason, someone up above, insist that filesharing sites are a source of virus, worms and their friends. So they throttle the network, until I fix it, by blocking it.

Another reason, is we are using a thin pipe, and we are using quite a lot of bandwidth. Which I think we are student, there is not much we can do. Either way, I have not much of a choice, but to track it.

Webmin have a utilities to gather bandwidth usage statistics, which have one problem, take s a lot of cpu cycle, and slow down a server and I have to kill it. Until I figure out how to reconfigure it.

MRTG can do that too. except, to check out each host, you need to have snmp agents install on them. Which I can't because it is a dorm, and the computer is private property. So here, mrtg is monitor the server only. Life is so simple, when this is a work space.

On the other hand, linux have a few utilities for this as well. The one I use, is iftop. Best describe as top for network. It is in repository for most distro. It can be used to check bandwidth usage of each host.

To call it, just type

iftop -i ethx

you should get all the data from that interface. In a ncurse interface.

But the data don't stay, when you restart the program it will start again. Nevertheless, still useful. For someone who can't use snmp for the task.