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Can't connect to external/public IP

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New Poster

Can't connect to external/public IP

Trying to run a web server and a game server off my pc for testing purposes with myself and a couple of friends and it seems that I can't connect to my own public ip which will prohibit myself from connecting to my own server(s). I believe xfinity is blocking this. I have checked and ports are open, also my friends can connect. Does anyone have a solution to this?

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Expert

Re: Can't connect to external/public IP

If you are talking about reaching your server from your LAN via your public IP addy, you can't. This is called NAT loopback / hairpinning, and it is disabled in the Comcast supplied gateway devices. You can Google NAT loopback for more info.



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New Poster

Re: Can't connect to external/public IP

So If I use a different device I can do this?

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Frequent Visitor

Re: Can't connect to external/public IP

You might need a gateway that better supports Port Forwarding, or a Modem with a separate Router which supports Port Forwarding. I've read in several places that Comcast's supplied gateways do not do well at this. I bought my own (Modem/Router) and run a server from within my LAN, works great.

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Frequent Visitor

Re: Can't connect to external/public IP

Also, you'll want to ensure that the port you need is NOT on Comcast's blocked ports list:

 

Ports Blocked on Comcast Network

 

If the port you need is NOT on that list, you absolutely can set this up, you just need better hardware than the rental...

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Frequent Visitor

Re: Can't connect to external/public IP

After re-reading your post and EG's reply a little more thoroughly, it doesn't seem like port forwarding is the culprit if your friends (from WAN) can access. Guessing some upgraded hardware is still your ticket, though. If I'm not mistaken, I can access my LAN server using WAN IP from other machines in the network, so I guess my setup does NAT Loopback correctly then.

 

If you're interested, I use:

 

I suppose it's not "cheap," but it sures feels (and works) better owning than renting.

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Expert

Re: Can't connect to external/public IP


@djdave238 wrote:

After re-reading your post and EG's reply a little more thoroughly, it doesn't seem like port forwarding is the culprit.


Whew..... Ya' had me going for a second there bud.... !!! LOLLLL !!!  



I am not a Comcast Employee.
I am a Customer Expert volunteering my time to help other customers here in the Forums.
We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Mark the post as Best Answer!