The telnet command is used for connection and communication with a remote or local host via the Telnet TCP/IP protocol.
You can enter a domain or IP address and try connecting to it via the chosen port. In case the port is not specified, telnet utility tries to connect via the default port 23.
The command is really useful in cases when you need to check whether the needed port is open on your computer and on the side of the remote host.
How to use Telnet
- For Windows
Telnet is disabled on Windows by default. To enable it, perform these steps:
1. Press the Start button > Control Panel:
- Go to the Programssection:
- Select Programs and Features> Turn Windows Features on or off:
- Scroll down the list available in the Windows Features window > check Telnet Clientoption > press OK> wait a few moments for the changes to be applied:
- Telnet is enabled now, so we can run it in the same way as other commands:
- Select the Startbutton > click on the Run
- In the command line, type in cmdand press Enter.
- After that, type in the following and press Enter:
telnet [domain name or IP] [port number]
telnet hostlag.com 80
If you see the blank output after that, you have connected successfully. To quit you can press CTRL + C or any key:
As a result of successful telnet, we can conclude, that the entered domain or IP exists, and the chosen port is open on your computer and on the side of the target host.
If connection has not been established, the following error will appear:
Possible reasons for it are:
- domain or IP does not exist/not available/entered with a typo
- the chosen port is closed by a security software or via network configurations on your computer or on the side of the host you connect to
- connection/networking issue has occurred