Minecraft firewall settings

[Wyndru]

Well there are a lot of posts from people having problems with it on the minecraft forums. But, there does seem to be hints that it does work for some. Some can only get it to work using direct connect and some cannot get it to work at all. Do you have to use direct connect or does it show up when you click on multiplayer?

Multiplayer. I basically do what is suggested on the wiki, and it just works.

Local area network

A LAN game is only accessible to other people in your local network (e.g. just the people also connected to your router/switch are able to connect to you) unless you setup port forwarding on your router, then people can direct connect with your IP and Port. (ex. 123.45.67.89:43787)
To open your current single player world for other players in your LAN, type the command /publish into the chat (note that this is still very restricted, e.g. you can't adjust the game options using the commandline) or access the Game Menu and click on the "Open to LAN" button. There you can select the gamemode for other players and whether they should be allowed to use Cheats. Both of these methods give you an IP for use, for example: "Local game hosted on hostname:12345". If you type /publish and want to change the default gamemode, type /defaultgamemode 1 for example. Note: two computers using the same Minecraft account name cannot connect with this method.
Now other players can either connect to your game using the link minecraft provided you or they can connect using the multiplayer menu with its new "Scanning for LAN-Worlds" section at the bottom.
On the technical side a minecraft client with an opened LAN game sends a UDP multicast to the local address 224.0.2.60:4445 every 1.5 seconds. Other clients then listen for this multicast to show your game in their multiplayer menu.

I don't have any software installed that might block requests other than the built in Windows 7 firewall, microsoft security essentials and malwarebytes antimalware pro. None of those apps seem to interfere.

There are so many different variables though, it could even be the routers blocking it. I'm using the Verizon fios supplied actiontec router, it appears that it automatically adds exceptions to certain ports (I see them get added for various games occasionally, and I've haven't been adding them), so I never had to do anything with that.

 

[CU]

Yeah, that is what I do but it doesn't just work. The multicast udp broadcast on 224.0.2.60:4445 announcing the game doesn't make it from host to client. I suspect the error is on my end, but I just don't know where or how to trouble shoot it. As I have already rulled out Windows firewalls I can only assume my wireless bridge or router is the problem. The wireless bridge doesn't have any setting for firewalls and I don't see anything in my router software (Gargoyle) about blocking multicast traffic either.

 

[Wyndru]

Yeah, that is what I do but it doesn't just work. The multicast udp broadcast on 224.0.2.60:4445 announcing the game doesn't make it from host to client. I suspect the error is on my end, but I just don't know where or how to trouble shoot it. As I have already rulled out Windows firewalls I can only assume my wireless bridge or router is the problem. The wireless bridge doesn't have any setting for firewalls and I don't see anything in my router software (Gargoyle) about blocking multicast traffic either.

Does it work over wired? What kind of wireless bridge is it? I've had a ton of issues with a simple "plug and pray" wireless bridge (I think it was a belkin). I eventually ended up building one with an extra wireless router I had and dd-wrt which works much better now.

 

[CU]

Both computers have a wired connection to a TEW-640MB that wirelessly connects to a TEW-652brp runnning Gargoyle firmware. I have not tried a straight wireless connection. The computers are upstairs and my router is downstairs hence the wireless bridge. I actually had a TEW-652brp running dd-wrt as a wireless bridge, but it was very unstable and support for it on dd-wrt's forums a year ago from the moderators was less then helpful. The setup I have now is very stable. Up time on the router is around 150 days and that is only because I switched ISP's and had to move plugs around for new equipment.