We have Comcast Business Class (not the same as Comcast residential) internet service running to our home in to a Comcast-provided SMC D3G-CCR cable modem. This modem is configured to serve DHCP, and has five static IPs. The network address is 77.XX.YY.0/29, and the gateway device (the SMC) is at 77.XX.YY.6. The LAN IP address of the gateway is 10.20.10.1
Attached to this gateway device are two routers, each with DD-WRT. One is 10.20.20.1, the other is 10.20.30.1.
Attached to 20.1 are several dozen computers including a webserver, several other servers, and internet-connected clients. The webserver is named
hurricane and is at 10.20.20.90. From outside the network, navigating to 77.XX.YY.6 brings up the website hosted on hurricane, as expected. So far, so good.
The other router, 30.1 has a server attached to it at 30.60 named
typhoon, which is intended to be an OpenVPN server.
The problem I'm having is figuring out how to route 77.XX.YY.5 (or something other than .6) to
typhoon. Right now when I go to 77.XX.YY.5, all I get is a 404.
I can't have OpenVPN on
hurricane because they both will have similar ports serving totally different content.
I think I know that having both the gateway and each of the core routers serving DHCP is likely a problem. But I'm afraid to turn off DHCP on the gateway without knowing really what I'm doing because I'm afraid I'll break things to the point where I'll have to call tech support.
How, in general terms, do I configure my three routers to serve Internet-facing sites the way I intend?
If you have particular experience with static IPs on Comcast Buisness gatways, I'd love specific advice; but all advice is welcomed here.