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So this is a very strange problem that I have never encountered before. Let me start with a diagram of the network.

enter image description here

The problem is I have a few servers that are on my modem. Each server is assigned static ips. (1.1.1.34, 1.1.1.35)

These servers are configured properly as I am able to reach them from the outside world, and I can ping to and from. So i know that they have internet.

The issue becomes when I try to access them from my computer that is on the same modem. This computer is assigned dynamic IPs based on the modem itself (10.1.10.15). You know your typical local IP address.

When i run CMD i am able to ping those servers which I am assuming that is because we are all behind the same modem. But when I actually go to a web browser to access either the software platform that is on ip 1.1.1.34 or a website that is on server 1.1.1.35 I have no luck. I am not even able to ssh into the servers from this computer. But I can however ssh from another computer from the outside world.

Thanks for your help in advance.

* UPDATE *

As I am troubleshooting myself I will continue to keep updated on here.

I also now have ruled out a desktop computer issue. As I just connected my laptop via wifi and the same issue persists. I cannot view those websites.

I am going to look into the modem on the network.

  • Without knowing all the details, I would suggest checking your sub net configurations. Make sure that everything that you want to be able to "talk" is configured in such a way that they are on the same sub net or within the same sub net range. We had an issue here where people in the lab who were on x.x.x.40 couldnt talk to the servers on x.x.x.29 even though they were on the same network. If this is not the culprit try renewing your IP's and giving it another go. I had a case where I could access my remote servers but not my gateway server. I simply refreshed the IP and it worked. – RickwhoPrograms Aug 15 '18 at 14:36
  • Yea I have renewed my ips several times. – Bill Aug 15 '18 at 14:39
  • I would have thought about the subnet as well. Which makes a little sense because they are on different subnets. The servers are on 255.255.255.248 and the computer was assigned 255.255.255.0. But the only place that doesnt make sense is that the servers are web servers so it shouldnt matter what subnet a computer is on. They should have the ability to be able to be accessed from any computer around the world. Which they are except my desktop. – Bill Aug 15 '18 at 14:41
  • well externally they are probably communicating through some additional routing, however Internally your "routing" is your router/switch however you have that all set up. for example I am more than likely not on the same sub net as any of the websites I visit, however I can access them via some entity. But if I was trying to communicate with something internally and we were talking on different channels then there would be a gap if that makes sense. Not to mention why don't you try changing the sub net just to verify its not the issue? unless of course you are hosting or something. – RickwhoPrograms Aug 15 '18 at 14:51
  • @RickwhoPrograms Yes sin a sense that makes sense to me. So the problem that I am facing with that is. 1. this is the same configuration that I had at the other location. The only thing that i did was change the statics. 2. If that was the case. I cant even go into any computer and change the subnetmask, because i get an error that it doesnt belong with the gateway. Then I change the gateway and I get an error that it is not the correct gateway and I loose internet. By the way the gateway that is dhcp is typical local 10.1.10.1 where as the gateway i configure on servers are 1.1.1.38. – Bill Aug 15 '18 at 15:03
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Since we figure out that WiFi box on the picture is Comcast's gateway and you was able to set up issued to you by comcast static IP's, it is means that gateway working in bridge (or to be precise - pseudo bridge) mode.

I advise you then to get some firewall/router/wifi and assign on WAN side static IP that left (from issued to you 5 of them) then hook it to Camcast's box and use you desktop PC behind this new router to avoid exposure of workstations on the LAN side directly to internet.

You would be still able to access comcast box via 10.1.10.1 address to manage its weird settings even if you would set extra firewall behind comcast box as I suggested. (You can also access comcast box via gateway IP address, but only in case if you are on the same public subnet, from servers for example.)

Also change default 'highspeed' password on comcast box, if one of your server might be compromised, attacker wouldn't be able to screwed up comcast box settings.

One more advise, - do not use WiFi feature on comcast box or use it only as a guest WiFi

  • Hey Man thanks for all of your help with this. Yes that seems to be the issue. As soon as I put a new router in and assigned it one of my statics and put my computers behind it everything worked perfectly. It is a very strange thing that comcast does. I even had a tech come out and asked him about and he had no clue and just said "Well, thats comcast for you." Lol Appreciate all of your help – Bill Aug 16 '18 at 14:46
  • @Bill I glad my answer helped you. I just want to point out, in case some1 else would have the same problem that information above related only to "new" comcast's modems that has WiFi on board. Those who still use old business SMC modem works completely differently, there no such "pseudo bridge" features. – Alex Aug 16 '18 at 15:11

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