Replica set authentication / Special case

I have a question related to authentication when using a mongodb replica set.

Is it possible to set a mongodb replica set, where an authentication is going to be required from any coming user (client), but without a key-file and authentication between the members of the set?

In this M310 course, the two lectures related to my question are: Enabling SCRAM-SHA-1 and Enabling Internal Authentication.

But looking at them again did not seem to give me an answer (to this particular case). I hope the question is clear enough and someone can easily answer by YES or NO.

No not possible

You can try it yourselves.Setup 3 node replica with --auth enabled and no keyfile.If i am not wrong they will go to recover status and you will see hearbeat fail messages(not authorized on admin…)

From mongo docs

Replica Sets and Sharded clusters

Replica sets and sharded clusters require internal authentication between members when access control is enabled. For more details, please see Internal/Membership Authentication.

OK. Thank you for the answer. Actually I already tried and hit a wall. I wanted to have confirmation by someone more knowledgeable.

As you know a mistake is always possible so I was careful.