||This article's tone or style may not reflect the encyclopedic tone used on Wikipedia. (August 2012)|
|Type||Bandwidth usage / System monitor|
|License||GNU General Public License|
iftop is a command-line system monitor tool that produces a frequently-updated list of network connections. By default, the connections are ordered by bandwidth usage, with only the "top" bandwidth consumers shown.
The iftop website gives the following description: "iftop does for network usage what top(1) does for CPU usage. It listens to network traffic on a named interface and displays a table of current bandwidth usage by pairs of hosts. Handy for answering the question 'why is our ADSL link so slow?'".
Some options to iftop are listed below:
-n don't do hostname lookups -N don't convert port numbers to services -p run in promiscuous mode (show traffic between other hosts on the same network segment) -b don't display a bar graph of traffic -B Display bandwidth in bytes -i interface listen on named interface -f filter code use filter code to select packets to count (default: none, but only IP packets are counted) -F net/mask show traffic flows in/out of IPv4 network -G net6/mask6 show traffic flows in/out of IPv6 network -l display and count link-local IPv6 traffic (default: off) -P show ports as well as hosts -m limit sets the upper limit for the bandwidth scale -c config file specifies an alternative configuration file
Some options while inside the iftop interface are listed below:
t toggles single line f Open option to apply an extra filter
top- the similar 'top' command
- netsniff-ng's ifpps top-like statistics tool
- List of Unix programs