Many Git servers authenticate using SSH public keys. In order to provide a public key, each user in OS system must generate one if they don’t already have one.
# Lists the files in your .ssh directory, if they exist $ ls -al ~/.ssh
If you don’t have an existing public and private key pair, or don’t wish to use any that are available to connect to GitHub, then generate a new SSH key.
$ ssh-keygen -o
Display the content of your public keys:
$ cat ~/.ssh/id_rsa.pub