Want to know your bandwidth usage? Or who among your network peers are using most it. Then install network top (ntop), with it you can monitor your network bandwidth usage using pretty graphs (rrdtool). Ntop installs out-of-the-box through YaST (I’m assuming you have SUSE). Enough talking!

Here’s how to install it:

1. Install ‘ntop’ using YaST. So dependencies will be included.
2. After installation, time to set the admin’s password and the user ntop should run after it initializes.

   rawswift:~ # ntop -A -u wwwrun

   If you want to access ntop’s interface from any computer in your network then edit the ntop’s configuration file and change the localhost IP (127.0.0.1) to the host’s local network IP.

   • Open ntop configuration file (as root):

     rawswift:~ # vi /etc/sysconfig/ntop

   • Change ‘NTOPD_PORT’ value:
     • From: NTOPD_PORT=”127.0.0.1:3000″
     • To (host network IP): NTOPD_PORT=”xxx.xxx.xxx.xxx:3000″
   • Then save it!
3. Now start ntop script

   rawswift:~ # /etc/init.d/ntop start

If you want ntop to start on boot time then enable it in the init process:

rawswift:~ # chkconfig ntop on

Open you web browser and in the address box put the ntop’s host address and port (3000). You’ll now be able to see the bandwidth monitoring:

rawswift:~ # links 127.0.0.1:3000

What I like about ntop is that is uses rrdtool to graph the bandwidth usage. Really useful in tracking who uses the most bandwidth.

And if you want to go extreme, install ettercap and use ARP poison to sniff all data frames on your local area network (LAN). But be careful with playing man-in-the-middle attack in a low end computers. It’ll definitely bog down you network.