IFTop is similar to top, but instead of mainly checking for cpu usage it listens to network traffic on selected network interfaces and displays a table of current usage iftop monitors to network traffic and displays a table of current bandwidth usage. An interface may be specified or, if not, it will listen on the first interface it finds which looks like an external interface. iftop must be run with sufficient permissions to monitor all network traffic; on most systems this means that it must be run as a root user, see sudo.
chaitanya-GA-78LMT-S2 ~ # iftop
IP address is: 10.7.70.12
MAC address is: 94:de:80:32:a9:46
Press h For Help
Print a summary of usage.
Dont do hostname lookups.
Do not resolve port number to service names
Run in promiscuous mode, so that traffic which does not pass directly through the specified interface is also counted.
Turn on port display.
Display and count datagrams addressed to or from link-local IPv6 addresses. The default is not to display that address category.
Dont display bar graphs of traffic.
Set the upper limit for the bandwidth scale. Specified as a number with a ‘K’, ‘M’ or ‘G’ suffix.
Display bandwidth rates in bytes/sec rather than bits/sec.
Listen to packets on interface.
-f filter code
Use filter code to select the packets to count. Only IP packets are ever counted, so the specified code is evaluated as (filter
code) and ip.
Specifies an IPv4 network for traffic analysis. If specified, iftop will only include packets flowing in to or out of the given
network, and packet direction is determined relative to the network boundary, rather than to the interface. You may specify mask
as a dotted quad, such as /255.255.255.0, or as a single number specifying the number of bits set in the netmask, such as /24.
Specifies an IPv6 network for traffic analysis. The value of mask6 can be given as a prefix length or as a numerical address
string for more compound bitmasking.
-c config file
Specifies an alternate config file. If not specified, iftop will use ~/.iftoprc if it exists. See below for a description of
-t text output mode
Use text interface without ncurses and print the output to STDOUT.