Secure Shell (SSH) is a cryptographic network protocol used for secure connection between a client and a server and supports various authentication mechanisms. The two most popular mechanisms are passwords based authentication and public key based authentication. Using SSH keys is more secure and convenient than traditional password authentication. In this tutorial we will describe how to generate SSH keys on Debian 9 systems. We will also show you how to setup a SSH key-based authentication and connect to your remote Linux servers without entering a password.