Reconnect to room on a Relay Server

Paul Winterhalder

Hi Alessio,

You should certainly be able to reconnect to the Relay Server instance - as long as it is still up of course. If you were the last player in a room, it's possible the relay server instance had terminated before you returned?

Out of curiosity - what client lib are you using... Unity? Unreal? Is it our latest libs?

Paul.

Paul Winterhalder

Also Alessio,

Can we get some more details on your use case - especially in terms of lobby configuration?

i.e. The relay server behaviour for disconnecting users is different depending on your lobby type... i.e. if it's a long-running lobby (i.e. "Disband on start" is false) the relay server sends a SYS_MEMBER_LEFT call to the api server... if it's not, we don't send that call.

More details will help us to better determine what may be happening for you.

Paul.

Alessio Falsetti

Hello Paul,
this is my scenario:

player A and player B enter the lobby
the lobby is set to READY and the ROOM_ASSIGNED and ROOM_READY events arrive
both players enter the ROOM and then start playing
in the meantime the lobby is DISBANDED ("Disband on start" is true)
player B disconnects for network reasons, player A receives the notification that the opponent has disconnected
player B tries to connect again to the room where player A is still present, but receives the error:
{"status":403,"reason_code":90300,"status_message":"Relay: Disconnected by server","severity":"ERROR"}. Player B uses the same access data received from ROOM_ASSIGNED (host, port, passcode)

We are using Unity and the client version of BC is 5.0.0.

Another question: is one server instantiated per ROOM, or can a single server host multiple ROOMs?

Thanks!

Alessio

Paul Winterhalder

Hi Alessio,

Thanks for the use case clarification - our folks are attempting to replicate the scenario. Certainly the intention is that that reconnect should work - the Relay Server should have the initial collection of members from the lobby cached.

Question - how are you disconnecting "Player B" for network reasons? Would it involve them re-authenticating - and thus getting a new brainCloud session? (If so - that changes the id we call their "cx" - which combines their profileId:sessionId - and is likely the reason the reconnect is failing).

If they were to reconnect without re-authenticating - it would probably work...

(Note - we haven't confirmed that yet - but it's our working theory.)

And to answer your question - yes, a server can host multiple rooms. It is controlled via the "Containers Per Server" property when defining the server on the My Servers page.

Paul.

Greg Moulds

Also Alessio, can you confirm whether your lobby type has the "Allow join in progress" Rule enabled or disabled? That's also relevant. Thanks!

Alessio Falsetti

Hi Paul & Greg,

player B re-authenticates, so I assume that his "cx" changes. Is it possible to ensure that the player can re-enter the room even by re-authenticating? If you have a unique passcode, could you use that?
"Allow join in progress" is true

Regarding the number of rooms, so in practice you can have a maximum of 2500 simultaneous rooms (50 "Max servers" x 50 "Containers per Server"), right?

Thank you!

Paul Winterhalder

Hi Alessio,

I think we've identified your test app and lobby. We believe that both

Disband at Start

Allow join in progress

are enabled for that lobby. Unfortunately - they shouldn't be - this is a regression in Portal-X - it should be disallowing that combo.

So what we believe is happening is player B is re-authenticating before attempting to re-connect.

Because Player B now has a new session, he/she also has a new connection id (i.e. cx) - and the Relay Server seems them as a new person.

Because "Allow Join in Progress" is enabled - the Relay Server attempts to contact the lobby to see if this user is valid - but that lobby doesn't exist anymore - and we get the error you are seeing... (which is maybe not the best error message).

Disabling "Allow join in progress" will result in a more understandable error message - but probably won't fix the problem.

The real trick to this scenario would be for the network re-connect to the room server to happen without recreating the CX - but depending upon the type of network failure that is probably unavoidable.

The devs are looking into options.

Paul.

Alessio Falsetti

Thanks Paul, I really appreciate it.
Bear in mind that the player could also disconnect due to a crash or the mobile device being turned off, so the possibility of re-entering the room even after having performed a new authentication would be very very important.

Please let me know!

Alessio

Paul Winterhalder

Also Alessio,

Agreed with your scenario - we are prioritizing a improvement to deal with that scenario for you.

Also that maximum # of servers is a limit that we can control per-app - so we can bump that up.

Paul.

Alessio Falsetti

Hi @Paul-Winterhalder, any chance to have new developments regarding reconnection in the room?

Paul Winterhalder

Hi @Alessio-Falsetti - checking with the devs.

I believe we have a short-term Relay Server patch that makes reconnecting generally more reliable -- but also a change for 5.2 that can allow reconnecting across sessions... (that will be an option for the dev to enable).

5.2 is currently targeting mid-to-late February for release.

Alessio Falsetti

Great! Happy to hear that!

Alessio Falsetti

Ciao @Paul-Winterhalder, @Greg-Moulds,
I have updated BC to 5.2, so I can implement the rejoin in the room. But it's not clear to me how to implement it. The only information I found is in the release notes where it only says this:

Reconnects - Relay Servers now better handling reconnect scenarios. There is also an option to allow reconnects even if the user’s session has changed ("ALLOW_REJOIN_BY_PROFILE_ID": "true").

How does it work?

Thanks!

Greg Moulds

Hey @Alessio-Falsetti . In order to enable that feature, you need to update the "Custom Environment" settings for the appropriate "My Servers" definition:

Alessio Falsetti

Hi @Greg-Moulds ,
ok, I've updated the custom environment of my server, and now? If I try to rejoin the room, I receive alway this error:
"status":403,"reason_code":90300,"status_message":"Server Closed Connection","severity":"ERROR"}.

I'm using:
RelayService.Connect(RelayConnectionType.TCP, connectionOptions, null, failureCallback);

What should I do?
Thanks!

Greg Moulds

Hmm... Let me poke around.

Greg Moulds

So a question for you... are you able to connect initially and it's failing on the reconnect? Or are you failing to connect at all?

Greg Moulds

I'm assuming from your statement "if I try to rejoin the room" that you've connected successfully initially.

Alessio Falsetti

Yes, works well first time.

Alessio Falsetti

However, reconnection doesn't work.