How to use telnet in linux to open ports

You can check out the other options by typing: man netstat Show the program to which the socket belongs The netstat command prints details of network connections, it has a lot of options, but these are the ones relevant to checking ports: If youвЂ™re logged into the computer you wish to see what ports are open on, use one of the following tools to see which ports are open: The netstatВ Command sudo netstat -tuplen Used when a temporary port number is required for a short-lived connection or private useД¬heck if a Network Port is Open From the Server Itself Ports registered with IANA for use with a designated application

Still, there is some standardization so that users donвЂ™t have to type the port number every time they connect to an online service and so that an educated guess can be made about what protocol should be used when connecting to a server.Д¬ommon network services like FTP, HTTP, SSH

The port tells the computer what process youвЂ™re trying to reach.ДЄ service can be set to respond on any port number. Each process can be assigned to one or more ports, but a port can only be assigned to one process.ДЇor example, HTTP runs on port 80 by default, serving up websites, and when you SSH to a computer, youвЂ™re probably connecting on port 22, which is the default for the SSH service. So weвЂ™ve explained that a port is used to connect to a server вЂ“ but what does that actually mean?ДЄ port is a number between 5 and is assigned by the computer to a process. There are a few methods for checking which ports are open on Linux, and we cover all these methods in this tutorial. ItвЂ™s useful to be able to find out what ports are open on your Linux server should you want to connect to one of the services being served вЂ“ and itвЂ™s also useful to be able to check what ports are open so that you can make sure that you arenвЂ™t sharing something you donвЂ™t intend to. When your computer acts as a server, such as a web server or a database server, that server process must listen on a port that other computers connect to.

How to use telnet in linux to open ports