A more elegant way to test port connectivity – netcat command

Most of the time people will ask, “How do I check whether the port has been opened?”. And the answer you will get is most likely to be “Use TELNET!” There’s actually another way of doing it, i.e. using the netcat command. Refer to the tutorial below:

https://www.digitalocean.com/community/tutorials/how-to-use-netcat-to-establish-and-test-tcp-and-udp-connections-on-a-vps

Also, you can refer to the full table of switches that you can use for the nc command below:

http://www.tutorialspoint.com/unix_commands/nc.htm

nc command can be used in both Windows and Linux/UNIX. For Windows, download the netcat utility here: https://eternallybored.org/misc/netcat/