I hope this solution helps anyone else who has issues getting their raysat slaves to pick up on their Mental Ray network renders.
I'm writing this because I just banged my head against the wall most of the day to find that none of the common official FAQ trouble-shooting guides solved my woe with Raysat.
Finally I noticed in my log file something about
"error 011513: slave 1 died at handshake"
I found the solution here, though it refers to 2015 it worked for 2016 as well:
https://www.fisheyestudio.it/en/blog-maya-rendering/185-mental-ray-2015-satellite-setup-problem
"To make the distributed rendering feature work in Mental Ray for Maya 2015 you have to manually install the Microsoft Visual C++ 2012 package on the computers that will run Satellite."
Once I installed Microsoft Visual C++ 2012 on my slave it worked fine.
(link is what I believe to be current version as of 20/1/2016)
I hope someone finds this helpful.
