Updates to the auth specification require that an authentication failure on a single general use socket must close all sockets in the pool. The mechanism to do this in the Go driver is to use the topology.Server.Drain method. Update the topology.Server.Connection method to check if the error returned from getting a connection from the pool is an authentication error. If it is, call the Drain method and return the error. This will ensure that the server's connections are all (eventually) closed.