I’ve tried this several times, so I have a general idea of the problem, but I haven’t looked into it further or read the documentation, so maybe the answer is obvious if you do this.
But I like to use systems where the error immediately tells me what’s wrong without having to go through the documentation.
I first tried running a non-Ubuntu Pro instance with an Elliptic Curve SSH key (as opposed to RSA). Here’s why:
It worked well.
Next, I tried running an encrypted Ubuntu Pro instance. I couldn’t connect. The error message stated that my SSH key did not have authorization.
I searched CloudTrail for other errors or issues and found none.