question

To be very candid, we get very few requests for hosting Photon Server, largely because it isn't a simple drop-in. It requires running a "shim" executable, which reads the command line parameters and writes them to a file that the actual server executable code then reads when it starts. Your shim then has to keep running until the Photon Server executable stops, since the executable our game wrangler launches is the thing we're monitoring to see when we need to shut down the server host machine.

Our server hosting was specifically designed for the model where you have an executable which will run as an instance, for N people (as defined by the game mode you choose). We run up to M instances per host machine, and let you choose that M value, as well as the EC2 server model you want to use. You also tell us how many instance slots need to be available at all times, since start-up of a new server host in EC2, loading the base image, and then loading the game executable (and associated files) takes several minutes - so you want to have capacity available for the largest number of players you think will need to join games in that period.

Within a single instance, you can sub-divide the players into any number of sessions - that's entirely up to your server logic. So it's certainly possible to have many "rooms" in a Photon Server, similar to the way the Photon Cloud operates.

For your specific questions:

1) I wouldn't describe their model as obsolete at all. You can run a matchmaking server either separately or in our server hosting, and use our matchmaker to get players to connect to it, and from there do the allocation of players to servers. If you're using our hosting, you should use a simple cryptographic signature system to give clients a token they can validate with the gameplay server they connect to (create the signature on your matchmaker with your private key, decode it on your gameplay server and check the contents). The way the PlayFab matchmaker works is that it returns an available slot across all active game instances, ordering the list by the absolute value of the difference between the statistic you specify (if you want to use ranked matchmaking) and the statistic set on the server.

2) Yes, if you need custom matchmaking, you would use that API to implement the logic needed on your custom matchmaker server.

3) See above - you can have a single instance handle any number of players, and subdivide those players into sessions however you need to.

4) Sure, you can use any external servers with our external server hosting API calls. But yes, in that case, you would be responsible for spin up/down of servers, as well as collecting any log and output files, as we do not have the necessary access to the servers in that model. But again, you can subdivide players into rooms/sessions any way you want to - it's your server logic, which you can use however makes sense for your needs.