Unity Networked gaming 2019… What happened to NetworkBehaviour, OnServerStart() etc

Question

After a long break, I am now trying to learn some basics in networked gaming in Unity. I've installed the latest beta client (because I want to ultimately make a network multiplayer game but it will be many months of learning and building barebone prototypes to ensure I can get game objects spawning correctly and be controllable by the correct client etc etc

I have some experience in Unet, by extending the NetworkBehaviour class. I don't remember exactly but there were things such as [Client RPC] and [Command] and also OnServerStart() methods etc.

But I am aware Unet is being removed. And I tried to extend my class from NetworkBehaviour (I also tried NetworkBehavior lol) and it doesn't recognise it anymore.

So what replaces OnServerStart() method and [ClientRpc] instruction? Ideally I want to use a Dedicated Server solution (which I will run on my own computer in order to play small tests online of my game). The game im trying to make to start off with is extremely simple. The 'player' is just a capsule which can shoot small cubes and give damage to other players. Also the player object 'you' are controlling will appear blue, but all the other players will be grey.

Using Unet I was able to make the above small game idea work. But now I am unable to.

Answer 1

As of right now, there is no production ready replacement for UNET. UNET is currently deprecated. UNET has four main components, HLAPI, LLAPI, relay server, and legacy matchmaking. The HLAPI will be last shipped with 2018.4 LTS and supported until early 2021. The LLAPI will be last shipped with the 2019.4 LTS and have support until Spring 2022.

Therefore, unless you’re using a beta, UNET is currently deprecated but in the engine as of writing this post (2018.3.8 is the current official release). If you’re having problems, make sure you import the correct namespaces.

The new networking system is currently in alpha. You can can read about it here and see the source here.

Here is the transition timeframe:

Currently, the official advice is:

What should I use if I am making a multiplayer game today or have already shipped a multiplayer game?

Already launched: If your game has shipped and uses our Relay service, it will continue to run as expected until at least Spring 2022. By that time, we will either extend the Relay service or provide a clear transition plan to new technologies.

To be shipped in the next 0-6 months: If you’ve already completed most of the work on your multiplayer game using the LLAPI or HLAPI, it is okay to ship it using the 2018.4 (LTS) or prior versions of Unity. However, P2P architectures of all forms struggle with scalability, inconsistent connection quality, and hackable clients, so we recommend most games move to a dedicated server model if possible.

To be shipped in 6+ months: You should immediately consider moving to dedicated servers to determine what it will take to create a server-authoritative version of your game. Stay tuned for more details soon about the upcoming Preview packages to build your game with the new networking, dedicated servers, and matchmaker.

From here.

Additionally, there are other networking alternatives such as Mirror which strives to mirror UNET while providing fixes and improvements.