telnet

Run Telnet on Git Bash

October 20, 2021

Although telnet is not used regularly since insecure, it’s a handy tool for testing ports.

For example, to check if a port 80 is open, you run this command.

$ telnet servername 80

Git Bash does not come with telnet, but you can use the Windows version by using winpty.

$ winpty telnet servername 457
Connecting To servername...Could not open connection to the host, on port 457: Connect failed

If port is open, you get an empty reply, just like in Windows.

August 17, 2021

Here are a few tools to check if ports are open from a remote host.

nc -zvw10 192.168.0.1 22
nmap 192.168.0.1 -p 22
telnet 192.168.0.1 22

You may have to install netcat and nmap if missing in your distro.

yum install nc
yum install nmap

October 10, 2018

You can test a network port connection using the “nc” command on Linux and “telnet” on Windows.

Format:
$ nc -zv domain.com port
C:\> telnet domain.com port

$ nc -zv domain.com 80
Connection to domain.com 80 port [tcp/http] succeeded!

C:\> telnet -zv domain.com 80
Connecting To domain.com...Could not open connection to the host, on port 80: Connect failed

For Telnet, if a connection is successful, it returns no message.