In this tutorial, we will show you how to install Telnet on Ubuntu 20.04 LTS. For those of you who didn’t know, Telnet is a protocol that allows you to connect to remote computers (called hosts) over a TCP/IP network using a client-server protocol to establish a connection. Telnet listens to all the requests by the user usually on TCP port 23, but you can change it accordingly.
This article assumes you have at least basic knowledge of Linux, know how to use the shell, and most importantly, you host your site on your own VPS. The installation is quite simple and assumes you are running in the root account, if not you may need to add ‘sudo‘ to the commands to get root privileges. I will show you the step-by-step installation of Telnet on Ubuntu 20.04 (Focal Fossa). You can follow the same instructions for Ubuntu 18.04, 16.04, and any other Debian-based distribution like Linux Mint.
Prerequisites
- A server running one of the following operating systems: Ubuntu 20.04, 18.04, and any other Debian-based distribution like Linux Mint.
- It’s recommended that you use a fresh OS install to prevent any potential issues
- A
non-root sudo useror access to theroot user. We recommend acting as anon-root sudo user, however, you can harm your system if you’re not careful when acting as the root.
Install Telnet on Ubuntu 20.04 LTS Focal Fossa
Step 1. First, make sure that all your system packages are up-to-date by running the following apt commands in the terminal.
sudo apt update sudo apt upgrade
Step 2. Installing Telnet on Ubuntu 20.04.
By default, Telnet is available on the Ubuntu base repository. Telnet command can be installed both in Ubuntu and Debian systems using the apt command:
sudo apt install telnet
Verify Telnet status using the following command below:
sudo systemctl status inetd
Step 3. Configure Firewall.
By default, Telnet runs on port 23. If any firewall is running on your system, be sure to enable the necessary ports:
sudo ufw allow 23 sudo ufw reload sudo ufw enable
Step 4. Using Telnet on Ubuntu.
The general format of the telnet command is as below:
telnet [hostname/ipaddress] [port number]
The below example command tests if port 153 is listening for the server’s IP address 192.168.77.21:
telnet 192.168.77.21 153
Output:
Trying 192.168.77.21... Connected to 192.168.77.21. Escape character is '^]'.
Congratulations! You have successfully installed Telnet. Thanks for using this tutorial for installing the Telnet on Ubuntu 20.04 LTS Focal Fossa system. For additional help or useful information, we recommend you check the official Ubuntu website.
