Cannot authenticate into mongo, “auth fails”

Question

I\'ve created an admin user for mongo using these directions:

http://docs.mongodb.org/manual/tutorial/add-user-administrator/

From the mongo client it looks

Answer 1

Check for the mongo version of the client from where we are connecting to mongo server.

My case, mongo server was of version Mongo4.0.0 but my client was of version 2.4.9. Update the mongo version to update mongo cli.