IFTop

By Jack Szwergold • September 14, 2015

Basic IFTop usage.

You can just launch IFTop with no options and it will show network traffic on the main network interface such as en0 (Mac OS X) or eth0 (Linux):

sudo iftop

Show the network traffic on a specific network interface with the -i flag:

iftop -i en0

Show the network traffic on a specific network interface with the -i flag and filter out sundry DNS request traffic:

sudo -i en0 iftop -f 'not port domain'

Check for port 80 (HTTP) traffic on en0:

sudo iftop  -i en0 -nBP -f 'port 80'

Check for port 548 (HTTP) traffic on en0:

sudo iftop  -i en0 -nBP -f 'port 548'

Check for port 445 (HTTP) traffic on en0:

sudo iftop  -i en0 -nBP -f 'port 445'