If this connection succeeds your command window will go blank, you can either terminate the session by pressing “control + ]” and then entering ‘quit’, or better yet from there you can issue commands to the server. For example we can enter the below command to attempt connect to on port 80: telnet 80 The command is used in the format of ‘telnet hostname/ip address port‘ and entered into either command prompt or powershell under Windows, or through the shell in Linux or Unix. Now that the telnet client is installed ( see my last post here if you have not done this yet) we can perform some basic network connectivity tests.
The telnet client is simple yet extremely powerful in helping us gain a quick idea of where a problem may lie with TCP connectivity, it’s one of my first go to tools to use when testing a network connection to a server. This post is a follow on from my post last week regarding how to install the telnet client.