U

Visitor

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2 Messages

Friday, January 7th, 2022 2:05 PM

Closed

secondary router

I am using a DD-WRT VPN second router connected to the XFi router LAN port.  It gets a WAN IP ok (172.16.12.106) but it appears to be blocked to incoming traffic.

I cannot figure out how to allow ping (ICMP) and port forwarding to this IP.

I would prefer to keep this configuration (as opposed to bridging) as it allows me to have two LANs, one with a VPN and the other without.

Any info about how this secondary WAN IP is configured is appreciated.

Thanks,

<EDIT: Removed Personal Information>

Accepted Solution

Expert

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110K Messages

3 years ago

@user_d1d860 @user_bb801b That's actually a private IP addy. 

If you are hanging a stand-alone / separate router off of the gateway device, and the gateway is not in *bridge mode*, you are cascading 2 routing devices which results in an undesirable "double NAT" condition on your home network. 
 
Google "double NAT" for info about its potential pitfalls.

(edited)

Accepted Solution

Visitor

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2 Messages

3 years ago

Thanks user_d1d860,

The double NAT info makes sense. I prefer this setup as it allows me to isolate VPN devices from others connected to the XFi gateway.

I found a workaround for my peer-to-peer device that is connected to the VPN router. I created a raspberry pi proxy server on the XFi network that is reachable from the VPN network.

A bit of a kludge, but it seems to work.

Expert

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110K Messages

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Contributor

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167 Messages

@user_d1d860 

Details on setting up pi proxy server please? Enjoy indulging pi as much as possible, especially post holidays.

:-) 

Expert

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110K Messages

@user_d1d860

Glad you got it sorted ! Marked "Solved" topic now being closed. 

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? Please mark an Accepted Answer!tick
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? Please mark an Accepted Answer!tick
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.

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Contributor

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167 Messages

3 years ago

Hey can you say "network diagram" :-)

That said couple questions; Would a switch between the Xfinity Gateway and the other router satisfy the requirement? Isn't IP address assigned dynamically? Why port forwarding?

 Alternatively, a WIFI router behind the gateway and and ethernet cable from there to switch may suffice?

Just my .2 cents

 Thanks and good luck.

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