Client immediately disconnecting when joining game

I’m trying to test my game’s multiplayer mode with 2 players, with different steam accounts, on different machines, and not connected to the same router (in different households). One of those players is hosting the game (is a listen server).
I’m doing this using the Steam Subsystem, and all the Host/Join game logic is taken straight from the ShooterGame project.

When trying to join an existing game by calling ClientTravel.
On the client, nothing happens when I do this, and the log doesn’t really tell me much:

[2022.01.01-21.25.09:363][505]LogOnlineSession: STEAM: Using P2P Data for Connection Serialization
[2022.01.01-21.25.09:363][505]LogGameMode: Display: Match State Changed from InProgress to LeavingMap
[2022.01.01-21.25.09:363][505]LogGameState: Match State Changed from InProgress to LeavingMap
[2022.01.01-21.25.09:363][505]LogNet: Browse: steam.76561199148184909/Game/Maps/Menu
[2022.01.01-21.25.09:363][505]LogNet: Display: SteamNetDriver_2147482506 bound to port 7777
[2022.01.01-21.25.09:364][505]PacketHandlerLog: Loaded PacketHandler component: Engine.EngineHandlerComponentFactory (StatelessConnectHandlerComponent)
[2022.01.01-21.25.09:364][505]LogOnline: STEAM: Adding user 76561199148184909:7777 from RegisterConnection
[2022.01.01-21.25.09:364][505]LogNet: Game client on port 7777, rate 100000

Note: I can see the log mentions “steam.76561199148184909/Game/Maps/Menu”. That is not the path for the map the server is in. Don’t know if that’s right or if it’s something else.

On the server, the log says this (I tried to join more than once):

[2022.01.01-21.20.37:618][691]LogOnlineSession: STEAM: Updating lobby joinability to true.
[2022.01.01-21.20.44:545][523]LogOnline: STEAM: Adding P2P connection information with user 76561198072699293 (Name: User 1 [0x110000106B3999D])
[2022.01.01-21.21.10:846][682]LogOnlineSession: STEAM: Updating lobby joinability to true.
[2022.01.01-21.21.31:020][104]LogOnline: STEAM: Removing P2P Session Id: User 1 [0x110000106B3999D], Channel: -1, IdleTime: 46.475
[2022.01.01-21.21.32:527][285]LogOnline: STEAM: Closing all communications with user 76561198072699293
[2022.01.01-21.21.32:530][285]LogOnline: STEAM: 76561198072699293 has been removed.
[2022.01.01-21.23.06:159][523]LogOnlineSession: STEAM: Updating lobby joinability to true.
[2022.01.01-21.25.03:423][596]LogOnlineSession: STEAM: Updating lobby joinability to true.
[2022.01.01-21.25.12:729][712]LogOnlineSession: STEAM: Updating lobby joinability to true.
[2022.01.01-21.25.13:188][767]LogOnline: STEAM: Adding P2P connection information with user 76561198072699293 (Name: User 1 [0x110000106B3999D])
[2022.01.01-21.26.35:007][586]LogOnline: STEAM: Removing P2P Session Id: User 1 [0x110000106B3999D], Channel: -1, IdleTime: 81.819
[2022.01.01-21.26.36:512][767]LogOnline: STEAM: Closing all communications with user 76561198072699293
[2022.01.01-21.26.36:514][767]LogOnline: STEAM: 76561198072699293 has been removed.
[2022.01.01-21.26.40:419][236]LogOnlineSession: STEAM: Updating lobby joinability to true.

My actual steam username was replaced with User 1.
Apparently, the server recognizes that I’m trying to join, but I’m immediately kicked as well, and I don’t know why.

Can someone help me with this? Please let me know if there’s any more information that can help track this down!

Thanks in advance!

This probably won’t do much but I had a similar situation where I could connect to a session, but instantly get removed with EOS OnlineSubsystem.

Do you have the correct IpNetDriver selected?

I think so?

[/Script/Engine.GameEngine]
+NetDriverDefinitions=(DefName="GameNetDriver",DriverClassName="OnlineSubsystemSteam.SteamNetDriver",DriverClassNameFallback="OnlineSubsystemUtils.IpNetDriver")

You got bInitServerOnClient=true in your Steam Subsystem section in the same config file?

I don’t!
I’ll try that!

I’m afraid this didn’t work.

Update: The fix for this was to add “?listen” to the TravelURL fed to the Host/CreateSession function!