For the purpose of a training session, I'd like to make it possible for a particular user to connect without requiring a password or key-based authentication. I do not know the IPs or other data of the people connecting up front.
Is it possible to configure OpenSSH's
sshd (or PAM) in a way to make this possible? How?
NB: The access will be time-limited and the access on the system will also be rather limited, so there is no need to point out security implications.