$ Linux Command

Network

iftop

Show live bandwidth usage by network connection.

networkbandwidthmonitortraffic

Additional Notes

iftop is a network command used to show live bandwidth usage by network connection. It displays a real-time, ncurses-based view of bandwidth usage per host connection.

iftop requires root privileges or appropriate capabilities to monitor all traffic. Use -i INTERFACE to target a specific interface.

Syntax

iftop [options]

Parameters

  • options: Flags that change how iftop behaves.
  • interface: Network interface to monitor (e.g., eth0).

Common Options

  • -i INTERFACE: Monitor a specific interface.
  • -n: Do not resolve hostnames.
  • -P: Show ports.

Examples

sudo iftop
sudo iftop -i eth0
sudo iftop -nP

Practical Notes

iftop is useful for quickly seeing which connections are using bandwidth.