If I want to test the failover in an FT environment, I should run the /install_dir/scripts/dadaemon maintenance command in the primary/active data aggregator server so that it fails over to the secondary/inactive server, but it does nothing.
I waited half a day to see if it fails over, but nothing happened. The only way I found to do this was by restarting the box.
I'm testing this in a fresh installation of PM 3.6