SSH key-based authentication

As we have noticed by using SSH every time, we need to type the password, which is not something recommended in many security policies. This is where we will use the SSH feature to use authentication by using public/private keys.

SSH provides a tool for creating public/private keys to use for remote connection authentication, without the need to use a password. How do we do that? It's simple. For this test example we are going to create a new RSA key, a little bit more secure than the usual (we can create different types of keys such as dsa, ecdsa, ed25519):

$ ssh-keygen –t rsa -b 2048 -v

Then we follow the steps presented by the command. For a default installation, we can just keep typing Enter. Otherwise, we can always add some kind of passphrase to make it more secure. We may need to specify the key file name so we can use it later.

Then we need to copy the newly created keys file to the host that we want to connect to. There are two ways of doing this. The...