I need to be able to access my external IP from an internal one. Currently when I try to, I am unable to access my private web server. I can access it locally and from a remote IP, but not from a local ip (EX: 10.1.10.10) to the external IP. Is there a setting I can change on the DPC3939B to allow this? I'm not seeing no option for it in NAT nor does static routs work.
Hello 8BitSloth and welcome,
Yes, this can be done. You need to log into your DPC, goto LAN status, then change the starting DHCP address to 10.1.10.10, click apply or save. This will then enable you to have a 10.1.10.2 through 10.1.10.9 for your dedicated DHCP interconnect for your server, et al. You will need to make sure your server IP address is configured to any 10.1.10.2 to 10.1.10.9 IP address, using 10.1.10.1 as the gateway, and subnet mask = 255.255.255.0. You server will need to be directly connected to any of the DPC LanPorts 1-4. This will allow you to achieve your objective.
Hope this helps you out.
Sorry to report, but it did not work for me. I followed your directions exactly and tried to access the stream on 10.1.10.5 from 10.1.10.15 and also tried using a VM on the same PC, just for kicks. None could access my external IP. I also forwarded port 80 since, without that, it was going directly to my modem's login page.
I am trying to run a basic rtsp server so I can share my desktop. The server is so basic, it can only bind to one IP. This means if I want it to point to the outside world, it will only be accessable from my external IP. This isn't a problem for people not on my network, but it prevents people inside from viewing the stream. In the past this hasn't been a big deal because I was running my own modem/router setup, but now I've got this new Comcast modem and it just can't seem to pull this trick off. I could change servers to something that can stream to more than one IP, but resources are currently limited on this PC.
Not sure if this is related, in the last week or so I am now unable to connect to my external IP from the rest of the world or internal network. I can ping it from external or internal but can't connect via port 80 or 443 or any other port. I'm looking here before I call support. See if you can connect to a simple service at your external IP externally. I used to be able to "hairpin" to my external IP address internally but this is no longer working, ping behaves normal both internal and external, see if you can ping your external IP from internal. I have a Netgear Comcast Business router but I think this is due to a network change upstream.