Network Question

[Taem]

My kids have been playing this game called Minecraft (should be Mind Crack because they play it so much). Anyways, they built their own server, but their computers are a bit slow, so I am hosting the server on my computer over the network. They can join my server over the network by connecting to my computers actual IP, however if someone tries to join the server from another network/internet, it simply won't work.

I went to this site, choosing my Router and Minecraft and I'm sure the settings are identical to what is on here, but still, no one can connect to our server unless they are on our network. I even downloaded a program to check the ports and everything is setup and ready to go - at least when the program checked the ports from my computer, which is on my network! I must be giving out the wrong IP, but which one is toe correct one? How do I find it?

I thought it might be Windows Firewall, but I know that's impossible because people already on my network can access the server just fine, even ones recently added. Thoughts?

[--Pete]

Hi,

I must be giving out the wrong IP, but which one is toe correct one? How do I find it?

Start a command window and run ipconfig /all

That should give you the IP address as well as all the pertinent information on your computers. Then, using the computers' IP addresses try pinging them to see if they can speak to each other.

If this is a Wi-Fi network, check to see if you've got MAC or IP filtering on, and if so, be sure that all the appropriate info for all the computers is entered on the router.

That's all that comes to my mind, but I'm sure that there are others here who'll be able to help you more.

--Pete

[[vL]Kp]

however if someone tries to join the server from another network/internet, it simply won't work.

What do you mean "another network"? I can understand that a typical home user would be behind a device that disrupts easy Internet connectivity, but I am curious how a secondary non-Internet network fits into this.

Windows Firewall could still be the problem. Though it is usually used in a simple allow/disallow mode, it can do more complex things, such as "Allow connections from the local subnet and disallow all others", which would produce this result.

Since you already mentioned a Linksys device, I suspect the IP addresses shown by ipconfig will be private LAN-local addresses, useful for connectivity within your private network, but not useful for allowing users on the Internet to join you. The port checking program likely worked because you ran it from inside your network, which we already know works. It would be more useful to have someone outside your network run it. When you give out the address to a non-local user, does it start with 192.168., 172.16.-172.31., or 10.? If so, that is a private non-routed address that will not work. You must give remote joiners the public IP address that is assigned to your Linksys router.

There are a few ways this could be failing:

• Linksys device fails to forward incoming connection from Internet to Minecraft server.
• Linksys device attempts to forward connection to Minecraft server, but is pointed at the wrong internal machine.
• Minecraft server is blocking non-local connections (via Windows Firewall, as described above)
• Minecraft server is immediately killing incoming connections (application-specific failure mode, may not apply in all cases)

[Taem]

I see three issues. First, I set my router to only accept MACs on the list. Second, my computer is connected wirelessly. Third, the ip does start with 192.168, or however that was - on droid so a little hard to review and text. So once I find my routers outgoing IP, how do I get users to connect to our server on my computer since we have five computers on the network and xbox and bluray player and droid phone... lol an printer? Also, will my router disallow users not allowed by their MAC, even though I opened up the port?

[kandrathe]

The HOST address out in internet space will be your Router's external IP address (probably assigned by your ISP, i.e. something like 24.34.122.56 ).

Firewall issues: By default, most firewalls block all incoming packets that are not a response to your outgoing requests. You need to ensure that the required transmission ports (TCP, UDP) are unblocked from your firewall/router and your host allowing packets going out, and allowing external Clients to transmit packets to you.

Routing issues: Then, you need to ensure that from your router the "Service" (by Service -- e.g. 192.168.1.1:1200 ) is routed to your local server (i.e. 192.168.1.100). In other words, when your router gets packets of that type (i.e. 1200), it needs to know that it should pass it along to your (192.168.1.100) server. Your local server will get external clients traffic (request packets) via the routers address, and then reply (response packets).

I usually troubleshoot my home server hosting issues by either working with a remote friend, or by accessing/investigating my home IP address from work (From home, I can VPN to work, and sniff back to my home network via remote).