Generate SSH Key

Check existing SSH keys

Generate a new SSH key

Add private key to ssh-agent

Add public key <fileName>.pub to the server eg. github.com

Test the connection with the server eg. github.com

(Optional) Make git use different keys based on hostname

1. Check existing SSH keys

        ls –al ~/.ssh

        # list all ssh keys if existing, one key pair can be use on multiple servers

2. Generate a new SSH key

        ssh–keygen –t rsa –C “email@me.com“ –f <keyName>

        # create a new ssh key pair using rsa algorithm, email as label

# and keyName as filename, id_rsa by default if not specified

# follow the prompt to enter file name(if not specified) and passphrase,

# at the end a fingerprint or id of the key would be given

3. Add private key to ssh-agent

• Ensure ssh-agent is enabled

                eval “$(ssh–agent –s)” # start the ssh-agent in the background

• Add new private key to the agent

                ssh–add ~/.ssh/<fileName>

4. Add public key <fileName>.pub to the server eg. github.com

5. Test the connection with the server eg. github.com

        ssh -i <fileName> -T git@github.com

        # i flag specifies the ssh file used, id_rsa would be used if not specified

        # T flag disabled pseudo-tty allocation

6. (Optional) Make git use different keys based on hostname

        Git does not have i flag like ssh to specify the key file to use, but we can configure git to use the corresponding key files based on the host we try to git.

• Create ~/.ssh/config file if not existing

        touch ~/.ssh/config

• Add these to ~/.ssh/config file

Host GitLab

    HostName gitlab.com

    User git

    IdentityFile ~/.ssh/<gitlab-filename>

    IdentitiesOnly yes

Host github

    HostName github.com

    User git

    IdentityFile ~/.ssh/<github-filename>

    IdentitiesOnly yes

• Test git connection

        Git should be able to pull/push if those keys are already added to the servers