MacOS – How to add a guest public ssh key for remote access

First, you create a public and private key (if you haven't done so already) on the machine from which you want to login:

ssh-keygen -t dsa

You only need to do this if there isn't already a ~/.ssh/id_dsa.pub file.

On Linux, there's the ssh-copy-id helper. On Mac, you need to copy the public key by hand:

• Copy the generated public key to the target machine:

  scp ~/.ssh/id_dsa.pub user@targetmachine:myPublicKey.pub

• Login to the target machine:

  ssh user@targetmachine

• Append the public key to the authorized keys:

  cat myPublicKey.pub >>.ssh/authorized_keys

• You can now delete the copied key:

  rm myPublicKey.pub

• Done. You should now be able to login to your target machine without the need to enter a password.

For starters, just to clarify the terminology, when you create a key pair, the private key (typically named id_rsa) goes on the client (in this case the Prompt app), and the public key (typically id_rsa.pub) goes in the ~/.ssh/authorized_keys file on the server you're logging in to (in this case your Mac).

You should be able to just drag the private key into Prompt via the iTunes documents interface. If you're getting a connection error, try doing it with your device attached via USB, not Wi-Fi (I've found Wi-Fi syncing can be a bit flaky at times). If that still doesn't work, open up your private key in a text editor, copy the text and send it to yourself in an email (or any other means that gets the text to your device). You can then copy that text, and when you click the key button in Prompt, it should give you the option to Import Clipboard Key.