@Override
    public Object attempt(Connection cnx) throws Exception {
      ServerQueueStatus status = cnx.getQueueStatus();
      return status.isNonRedundant() ? Boolean.FALSE : Boolean.TRUE;
    }
a "fake" operation which just extracts the queue status from the connection
geode-core/src/main/java/org/apache/geode/cache/client/internal/ExplicitConnectionSourceImpl.java