linux Program to Study LAN Traffic

[EdH]

What are some suggestions for linux programs to see local traffic within a LAN?

Specifically, I'd like to see how much bandwidth is in use for each of my "farm" machines. I sometimes see a limited download speed and would like to determine if it's my service or my machines.

[chalsall]

Originally Posted by EdH

What are some suggestions for linux programs to see local traffic within a LAN?

For deep work, make friends with tcpdump. Wireshark for a GUI, to drill down.

For "real-time" monitoring, "nmon" has a lot of very nice "panels" available for CPU, Disk, Network and RAM (console based).

[EdH]

Originally Posted by chalsall

For deep work, make friends with tcpdump. Wireshark for a GUI, to drill down.

For "real-time" monitoring, "nmon" has a lot of very nice "panels" available for CPU, Disk, Network and RAM (console based).

Thanks! I'll check these out. I currently use nmap to see if a system is "missing," but I'd like to see a little more detail per machine.

[chalsall]

Originally Posted by EdH

Thanks! I'll check these out.

You're most welcome. IMO, tcpdump is a required tool in a networking geeks toolbox.

When I'm in a new network, I will often run a "tcpdump -nli any -s 65535 -w datestring.tcp" command to "sniff-the-wire", and see what the other participants on the network might be doing...

Another thing... If there's a particular host pairing, protocol type, etc you're interested in something you can do is add an IPTables rule, and then do an "iptables -nvL | less" to view the counters (both packet counts and bytes).