I am the type of administrator that to check that a certain port is open I rarely think as a first option in Nmap or in nc (although this second is made specifically for that), the years got me used to using telnet.
The problem is that when I access a port using telnet and it is open, well, the port is open ... but then the damn telnet won't let go of me, it won't let me go ... ¬_¬ … No matter how hard I press Ctrl + C I only get a ^ C in the terminal, but no progress to exit.
Simple, we must press Ctrl +]… yes yes, Control key and without releasing it we press a closing bracket 😉
CTRL + ]
This will display the terminal or telnet console, in which we write quit and press Enter.
I don't know about you, but I didn't like at all having to close the terminal (or tab) because the damned telnet wouldn't let me go ... now no more, no more telnet tyranny !! (I.e.
Well nothing, it's something simple but damn it helps, enjoy it!