iftop command w/ examples in linux

it iftop The command guide follows my previous 90 Linux Commands Frequently Used by Linux Sysadmins article. Over time, I will continue to publish articles on about 90 commands geared towards Linux sysadmins and Linux power users. let’s continue this series iftop Permission.

iftop is a terminal program that displays network activity and details in text form. It is suitable for users who want to monitor network traffic without the overhead of a graphical interface.

general syntax of iftop The order is:

dstat [-afv] [options..] [delay [count]]

iftop linux install

Debian/Ubuntu and derivatives, use:

apt install iftop

RHEL/CentOS and derivatives, use:

dnf install iftop

Arch Linux and derivatives, use:

pacman -S iftop

iftop command example

To show bandwidth usage, use:

sudo iftop

To show the bandwidth usage of a given interface, use:
(replace with your interface)

sudo iftop -i eth0

To show bandwidth usage along with port information, use:

sudo iftop -P

To exclude, use a bar graph of traffic:

sudo iftop -b

To exclude hostname look ups, use:

sudo iftop -n

To display I/O traffic from a subnet, use:

sudo iftop -F 192.168.1.0/24

To sort traffic analysis data by source address, use:

sudo iftop -o source

To sort traffic analysis data by destination address, use:

sudo iftop -o destination

To monitor HTTP traffic, use:

sudo iftop -i eth0 -f 'port http'

To monitor HTTP traffic, excluding a specific host, use:

sudo iftop -i eth0 -f 'port http and not host 192.168.1.11'

To monitor DNS traffic, use:

sudo iftop -i eth0 -f 'port domain'

To monitor ICMP traffic, use:

sudo iftop -i eth0 -f 'icmp'

To monitor network traffic but ignore broadcast packets, use:

sudo iftop -i eth0 -f 'not ether host ff:ff:ff:ff:ff:ff'

Shortcut to change display options while running:

• h – Toggles the Help screen.
• s – toggles the source host display, and
• D – Toggles the destination hosts.
• s – Toggles the port number.
• n – Toggles name resolution.
• n – toggles the port resolution; Toggle resolution off to see all port numbers.
• Tea – Toggles the text interface. Default display requires ncurses.
• P – Pauses the display.
• Why – Leaves the program.

Useful links/references:

Related orders: