Add SSH key to the ssh-agent

To configure the ssh-agent program to use your SSH key, first ensure ssh-agent is enabled.

# start the ssh-agent in the background
$ eval $(ssh-agent -s)
Agent pid 59566
If you are using Git Bash, turn on the ssh-agent with command shown below instead:

# start the ssh-agent in the background
$ eval `ssh-agent`
Agent pid 59566
Then, add your SSH key to the ssh-agent:

$ ssh-add ~/.ssh/id_rsa