$ ssh-keygen -p
# Start the SSH key creation process
> Enter file in which the key is (/Users/you/.ssh/id_rsa): [Hit enter]
> Key has comment '/Users/you/.ssh/id_rsa'
> Enter new passphrase (empty for no passphrase): [Type new passphrase]
> Enter same passphrase again: [One more time for luck]
> Your identification has been saved with the new passphrase.
If your private key is not stored in one of the default locations (like ~/.ssh/id_rsa or ~/.ssh/id_dsa), you'll need to tell your SSH authentication agent where to find it. 要将密钥添加到 ssh-agent,请输入 ssh-add ~/path/to/my_key。 更多信息请参阅“生成新的 SSH 密钥并添加到 ssh-agent”
> Initializing new SSH agent...
> succeeded
> Enter passphrase for /c/Users/you/.ssh/id_rsa:
> Identity added: /c/Users/you/.ssh/id_rsa (/c/Users/you/.ssh/id_rsa)
> Welcome to Git (version 1.6.0.2-preview20080923)
>
> Run 'git help git' to display the help index.
> Run 'git help ' to display help for specific commands.