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So, I'd like to run a L4D2 game server on a VM. Partially for playing and partially for training. This is a simple residential network with a DSL modem and a E4200 router (for now). The router uses DHCP reservation to make the VM x.x.x.150 and uses the MAC of the VM to know that he's a DMZ. The modem is set such that the router is a DMZ (suspect problem).

So, when i start the game server, the start-ip script has "-ip x.x.x.150" which works on the LAN, but not the WAN. Then, when I set the start-up script for "-ip [external ip]", it just kicks back with:

WARNING: NET_OpenSocket: bind: Cannot assign requested address
Couldn't allocate any server IP port, tried 1 addresses

So, what I think I need is to set the server's network interface to the [external ip]. I vaguely remember a friend who's game server was setup this way. Anyway, I cannot figure out how to get the DMZ server's address to be the public ip. I've attempted to force a static ip, but I have no idea what the gateway should be.

I've Google'd the heck out of this for 2 days and found nothing except enterprise-league workarounds.

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migrated from Aug 10 '12 at 2:01

This question came from our site for system and network administrators.

You need to perform port forwarding on your router.

Firstly, you need to know the ports that your application (L4D2) is working on. Probably from this range 27000 - 27040.

Then goto your router's configure and perform port forwarding to these ports (TCP/UDP).

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Nice suggestion, but the idea of a DMZ is that all ports are open... – reasra Aug 11 '12 at 18:36
@reasra do you want to place your PC in the DMZ? – humansg Aug 13 '12 at 2:47
It's not the PC that's the DMZ, but the VM in it. Would a virtual interface work? I've never set one up. – reasra Aug 14 '12 at 1:06
Try troubleshooting from the router itself. First, look at the DHCP client table. Ensure that the router is assigning your VM an IP. Verify from this table the MAC address (of your VM) with the MAC address configured on your DMZ setting. – humansg Aug 14 '12 at 2:08
Anyway, I cannot figure out how to get the DMZ server's address to be the public ip From my knowledge, you cannot set the VM to the public IP. The purpose of the router there is to do a NAT translation for you. – humansg Aug 14 '12 at 2:11

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