I have a firewall set up with a stripped down RH 8.0 install. No GUI packages, all text based. The box has 2 NIC cards, and I'm using netfilter/iptables to control the firewall. The box is remote, and I log in and check it once in a while via SSH.

The firewall actually connects 2 internal networks together, both are 100Mbit, as are both the NIC cards. Users stream video through this server, sometimes using quite high bandwidth.

Is there a simple command I can use to monitor the REAL TIME usage and traffic level on this box? I can use "ifconfig" to see the quantity of data transfered over time, and I can see how many packets traversed the firewall via iptables counters, but I can't find exactly what I'm looking for.

I want to see a command that will spit out something like:

eth0:
Current: 24.8 Mbps / 25% capacity
Average: 15.4 Mbps / 15% capacity

eth1:
Current: 21.8 Mbps / 22% capacity
Average: 12.4 Mbps / 12% capacity

----

Is there any such beast built into linux? I can watch my network traffic in Performance/Networking monitor on my Win2k box, so I figure there MUST be something like this from the command line in linux also??

Thanks!!

Have you looked at MRTG. this gives you a graphical representation of bandwidth usage on your browser.

The backend requires MRTG and apache.

Im looking for something like this too, I host a pptp server and would like a real time monitor of who is using how much banwidth. Normally I just have to keep typing ifconfig all the time and read though everything, but I would like a program that I could use on telnet and updated in realtime. Basicly something like top. Top displays a realtime resource usage.

how the syntax of ifconfig can show the result like yours?