Handy CLI Utilities

powertop — power monitoring utility

lsof — lists open files and the processes that opened them

iftop — Network monitoring utility, very simple to read. It shows first-hop sources and destinations and all the expected stats

ncdu — NCurses Disk Usage, a curses-based version of the well-known du, providing a fast way to see what directories are using your disk space. Has interactive deleting capability.

pv — Get a running progress bar. With pv installed, let's assume you want to clone a 20GB drive, /dev/foo, to another drive (20GB or larger!), /dev/baz

sudo dd if=/dev/foo bs=4M | pv -s 20G | sudo dd of=/dev/baz bs=4M

Note that the bs=4M argument sets the blocksize for dd operations to 4MB, which drastically improves the speed of the whole thing. And the -s 20G argument tells pv how big this operation is expected to be, so it can give you an ETA as well as a current speed.

goaccess — Fast web log analyzer and interactive viewer.

goaccess /var/log/apache2/access.log --log-format=COMBINED

iperf3 —Tool for performing network throughput measurements. It can test TCP, UDP, or SCTP throughput. To perform an iperf3 test the user must establish both a server and a client. ettercap Interesting tool for network sniffing using ARP poisoning. Install as ettercap-text-only. There is also a graphical version, ettercap-graphical. See https://www.ettercap-project.org/, https://eatingsecurity.blogspot.com/2011/02/using-ettercap-for-arp-poisoning.html, https://www.thegeekstuff.com/2012/05/ettercap-tutorial/