To do fail-over with the Wowza Live Stream repeater system, the backup has to be running. One way to do this is in the .stream file on an edge server: you can put two origin urls separated by a |
The fail-over timeout is 12 seconds. You can modify by adding this property to the edge Application.xml /MediaCaster Properties container:
But there is not a way in Wowza to do on-the-fly fail-over, as you describe. The backup has to be running already.