I am using the mongo hadoop connector which uses the splitVector command (https://github.com/mongodb/mongo-hadoop/blob/master/core/src/main/java/com/mongodb/hadoop/splitter/StandaloneMongoSplitter.java#L94). I would like to force this command to be run against a secondary in my replica set but splitVector isn't a member of the "OBEDIENT_COMMANDS" which it looks like it needs to be in order to return my requestedPreference (secondary). Is there any reason why splitVector can't be added to the OBEDIENT_COMMANDS? Maybe there is another way of working this issue? Let me know if I can provide any more information.