How To Connect To An OCI Linux Instance Using SSH Password Authentication Instead Of SSH Keys
How to use password based authentication instead of ssh keys to log into a Linux OCI or OCI-C instance.
SSH key-pair authentication is more secure than password-based authentication, and it is the recommended configuration for a user logging in to an instance via ssh. It is assumed that the user account you want to change to using password-based authentication already exists and has previously been configured to use an SSH key-pair to log in to the instance.
Enabling password based authentication for a specific user does not prevent them from using a correctly configured SSH key-pair to log in to an instance via ssh, it just adds an additional method of authentication that the user can use when logging in via ssh to the instance.