How to set up ssh root login?

Question

SSH

The correct security policy reads:
1. Deny root login
2. Login not by passwords but by keys
If you do this in the ssh configuration, then after logging in inside the system we enter the root password already in sudo or su.
I want to log in as root by key.
How can I do it inside by logging in from outside via ssh without root?
Needed to automate Ansible, etc.

Answer 1

ssh to localhost