Autodesk explains.
Basically, you just have to connect all the needed machine together via ethernet cables, and pick one to be the manager, and one (or more) to be the servers.
There should be, in the Autodesk folder of program files, another folder called backburner. Launch the manager application on the manager computer, and the server application on all the others. I find that entering the name of the computer, rather than the IP address or subnet mask, works best. (just un-check the box that says "Automatic search" under the general settings.)
Then open 3ds max, and open the rendering dialogue. You have to set the file render location to a network accessible (IE, shared) location. Then, click the box that says "Net render" and click render.
Then you type in the name, IP or subnet mask of the manager computer, and click connect. That should do it.
You can also open the backburner queue monitor to manage and monitor the rendering process. (You'll have to connect the monitor to the manager to do this.)
BTW, you DO realize that the net render took almost twice as long? But don't worry, that's just because I only had two machines running it, and I think only one was working properly. If I had three or four, it would've taken much less time.
If the good lord had intended us to go outside or have a social life, he wouldn't have invented the internet.
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