About the unknown key type
error
When you generate a new SSH key, you may receive an unknown key type
error if your SSH client does not support the key type that you specify.
Prerequisites
You must have Homebrew installed. For more information, see the installation guide in the Homebrew documentation.
Solving the issue
Warning: If you install OpenSSH, your computer will not be able to retrieve passphrases that are stored in the Apple keychain. You will need to enter your passphrase or interact with your hardware security key every time you authenticate with SSH to GitHub or another web service.
If you remove OpenSSH, the passphrases that are stored in your keychain will once again be retrievable. You can remove OpenSSH by entering the command brew uninstall openssh
in Terminal.
- Open Terminal.
- Enter the command
brew install openssh
. - Quit and relaunch Terminal.
- Try the procedure for generating a new SSH key again. For more information, see "Generating a new SSH key and adding it to the ssh-agent."