The error message for errors with the code NotPrimaryNoSecondaryOk (aka NotMasterNoSlaveOk on older server versions) currently still is “not master and slaveOk=false”. We should consider rewriting it, even though we are not the ones generating the error message, both in the context of removing offensive terminology and in that we can provide a better error message with a concrete suggestion for the user here (e.g. pointing towards `db.getMongo().setReadPref()`).