I created a new instance via the Google Cloud web console from a CentOS 6.x image. I saw a blank on the creation form where I could paste in an existing SSH key; since this was my first instance, I didn't have one yet. I assumed it would take me through the key creation process like Amazon EC2 does. It didn't.
The instance appears to be created, but I can't figure out how to get the SSH key for it. The instance web page has a button that says "SSH" and it let me log in briefly via a pop-up web browser window that simulates an SSH session. However, it only let me into a user-level account, not
root. The pop-up had a menu item to change the user and changing it to
root does nothing but generate connection errors. Now I can't log into my instance at all!
I've searched but can't find any straight-forward documentation that explains this aspect of Google Compute instances.
Do I have to create my own SSH keys manually and paste them into the form during instance creation? Is there an obvious step I'm missing?