You can also use Bandwidth Monitor (bwm) to give you a rough idea of realtime bandwidth usage, something like this....
Code:
Bandwidth Monitor 1.1.0
Iface RX(KB/sec) TX(KB/sec) Total(KB/sec)
teql0 0.000 0.000 0.000
lo 0.000 0.000 0.000
dummy0 0.000 0.000 0.000
eth0 0.098 0.000 0.098
teql1 0.000 0.000 0.000
eth1 0.000 0.000 0.000
Total 0.098 0.000 0.098
Hit CTRL-C to end this madness.
Regards
ed