Issues while using network rendering and animation

[kavorka]

We have been using the new network rendering for some of our animations and there are a couple of things that keep happening.

1. It seems that if any of the GPUs that are connected fail, the master tries to collect their samples but can't. The animation hangs at that frame with a little bit of samples left but never finishes the frame. (We have had it hang a couple of times and it more than once it was when a GPU failed or a slave became unresponsive but it may be unrelated)

2. If you for some reason forget to put something into the output (ya, I did it more than once...) it will render out everything but just not save each frame. Could you put an error message that lets you know there is nothing in the output?