I have a 4 port 802.3ad "trunk" setup on a file server. While trying to troubleshoot someone else's machine with the same 4-port NIC, I ran iptraf on my (properly working) file server.

iptraf only shows one of the 4 ports doing anything, but the blinky lights on the switch & on the card itself tell me otherwise. I'm guessing that iptraf can't see all the interfaces (in my case, eth2 through eth5) as doing anything individually because they are all bonded as one interface... that being the case, it shows activity for all ports on the first port (eth2).

Can anyone confirm that my assumption is correct? Or is my bond not working properly?

Are there better monitoring tools so I can check throughput on each port?

I'm digging up all my old posts on this topic to help anyone else that may find them through a search...

You can monitor 802.3ad (or any other link aggregation protocol) using the program iptraf. It works pretty well & is bundled with most distros. I had a problem compiling it under 64bit Suse, but solved the problem by modifying some of the code. If that problem is still in the latest revision, send me a PM and I'll send you the necessary changes.