Bash - Monitoring Network Usage.md

Network Monitoring Management Tools:

These're just a few following network monitoring tools in Linux -

• nload
    nload is a command-line tool that displays the network usage on the system.
    It belongs to the category of network monitoring tool in Linux that simply sum up all the network traffic on a network interface.
• speedometer
    speedometer is a network monitoring tool.
    Similar to nload, it doesn’t differentiate the network traffic on a network interface by socket or processes.
    However, the display of speedometer is much more customizable.
• iftop
    iftop is a command-line tool that displays network usage by listening to the interface.
    In contrast to nload and speedometer, it monitors the network usage on each socket.

  To install iftop on Debian based Linux, we'll use apt-get as follows:

$ apt-get install -y iftop

  To install iftop on RHEL based Linux, we'll use apt-get as follows:

$ yum install -y epel-release  
$ yum install -y iftop

• nethogs
    nethogs is yet another command-line tool for monitoring network usage.
    It groups network traffic on a network interface by the process ID that generates or receives the network traffic.
    As a result, we’ll be able to monitor the network bandwidth consumption of different processes.
    to install:
    on Debian based Linux - use apt-get install -y nethogs
    on Redhat based Linux - use yum install -y nethogs

  $ nethogs

  
     The above screen shows the bandwidth consumed by each process.

  To change the refresh interval, we can use the flag -d:

  $ nethogs -d 2

  Trace mode:

  $ nethogs -t

  In trace mode, the reports are generated and appended to the console output.
  Therefore, providing us a stream of reports over time that can be used for further processing.

Reference:

1. https://www.baeldung.com/linux/monitor-network-usage