Are Read Preferences set automagically then or is it something that the application has to set depending on the situation?
As mentioned during the course, if we shutdown 2 of 3, we end up with a node that is a secondary. What can you do with the ‘surviving’ secondary node? Can you read write on it? From the course, it says do rs.slaveOk to read the data, I presume you can only do read only on the last surviving secondary node? Presumably, there is a way to make it primary and read/write, maybe just not covered on this course?