15. Basic tests of computer networks

15.4. nc

Netcat (nc) is a command executed in a terminal. It is available on Linux and macOS It can be used to test the operation of multiple TCP ports on a remote server simultaneously.

Example:

in Linux trminal I type:

nc -z -v 10.10.10.1 22

The command returns the result:

Connection to 10.10.10.1 22 port [tcp/ssh] successful!

This means a successful connection to host 10.10.10.1 on TCP port 22