Solved [Mostly] Interesting inability to connect.

[mrbaggins]

I have a server at ip #.#.65.221. It is running FTB Magic Farm 2.

I have a client at ip #.#.65.53. The machines can communicate, both can ping each other fine.

The server is up and running. It runs all it's commands fine. Testing at home on localhost I can connect.

When the client clicks "Multiplayer" the server pops up in the list with 24ms ping, full green bars, and 0/20 players. Trying to enter the server the game halts for about 15-20 seconds, then gives a java.net.connectException: Connection timed out:connect.

Meanwhile, the server shows "[info] playername [/#.#.65.53: PORT] lost connection.

I've disabled firewalls on both machines, I've tried adding java, the launcher, full TCP/UDP port ranges in and outbound to the rules. The machines can ping each other fine, both seem to connect in everyway (including the server browser) but as soon as a direct connection is attempted it fails.

Any ideas?

 

[mrbaggins]

Solved. Ish.

I'm behind a proxy at this location. Whilst MMC5 supports HTTP proxy, allowing authentication with the Minecraft servers for each player, the server does not, meaning it tries to check sessions.

Going to offline mode works. It still forces clients to need a valid account (MMC does the forcing) but someone with the right modlist and configs in another launcher could connect and make life interesting.