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forwarding one port to another

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nybble
Visitor

forwarding one port to another

I have the CBR-T gateway and, while I can forward ports, it seems that I only have the option to forward from port X to port X, not port X to port Y. I have multiple web servers running on my internal LAN and want traffic that comes in on my static IP to go to port 80 for each of the servers, determined by the incoming port. For example, from xx.xx.xx.xx:1117 to 10.1.10.20:80 and xx.xx.xx.xx:1119 to 10.1.10.21:80. Is this not possible with this gateway?

Accepted Solution

Re: forwarding one port to another

I know that the port forwarding would be an option on the gateway in general, but setting it up would be outside of our demarcation. If you are able to find a solution, can you please update this forum so it might help someone else in the future? We'd appreciate it!

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Official Employee

Re: forwarding one port to another

Although we can assist you by making requested changes on your leased modem, most of these settings fall into the realm of the customer’s local network and are beyond our demarcation of support.  . Port forwarding will only work if the local machine that you want traffic forwarded to is assigned an IP address in one of the private IP subnets:

  • 10.x.x.x

  • 172.16.x.x - 172.31.x.x

  • 192.168.x.x

Please let me know if I can address any further questions or concerns. 

nybble
Visitor

Re: forwarding one port to another

Thanks for your reply. I know how port forwarding works, however the equipment I am currently leasing seems unable to forward from one port number to a different port number. Is it possible to swicth my gateway/router with another model that supports this feature? Perhaps I need to call my service rep?

Official Employee

Re: forwarding one port to another

Your service rep handles sales concerns and would not be able to assist with the technical aspect. Can you please private message me with the name, address and phone number on the account? 

nybble
Visitor

Re: forwarding one port to another

Anyone else have thoughts? The port forward is working correctly, however it is not the port forwarding I need. Does anyone know if any Comcast hardward will forward a port "X" to a port "Y" instead of just X to X?



 

Official Employee

Re: forwarding one port to another

What is the make and model of the leased gateway? Also,although this forum thread is older, it may still be of use: https://forums.xfinity.com/t5/Your-Home-Network/Port-Forwarding-for-an-IP-Camera/td-p/1529477

nybble
Visitor

Re: forwarding one port to another

The gateway is a Technicolor CGA4131COM.

 

The thread is helpful in that it shows what I want to do: setup up an external port to a *different* internal port. It's just that I'm pretty sure my gateway does not have that feature.

Official Employee

Re: forwarding one port to another

This link has the information we can assist with as far as the port forwarding and configuration: https://business.comcast.com/help-and-support/internet/comcast-business-ip-gateway-static-firewall/#... . If those do not allow you to set it up the way that you described, you'd want to reach out to your local IT for further assistance. 

nybble
Visitor

Re: forwarding one port to another

No, they do not. There is nothing I can find in any documentation for my gateway that allows me to forward from one external port to a different internal port. I guess I will have to call Comcast's business technician.

Official Employee

Re: forwarding one port to another

I know that the port forwarding would be an option on the gateway in general, but setting it up would be outside of our demarcation. If you are able to find a solution, can you please update this forum so it might help someone else in the future? We'd appreciate it!

oatmeal
New Member

Re: forwarding one port to another

Yup, I am going through this same rigmarole right now.  Comcast support is unhelpful.

 

They just pulled my SMC modem out of my office this morning and replaced it with the technicolor/cisco unit during a service upgrade.

 

My solution? Request that they bring the SMC unit back as the SMC provides the option to specify the Public Port and Private Port ranges whereas the technicolor/cisco unit only provides the Start and End Port ranges but does not allow you to forward public port X to private port Y.