connecting my night hawk in to my Xfinity router in series

[PapaVito]

Can I just run the night hawk router In serier with my existing xfinity router, so i don't have to establish a whole new network or password. Was hopping I could just plug the eathernet from one to the other? My Xfinity has a wall pod that meshes my 2.4 and 5 GHz together. will I need to unplug that? 

[plemans]

It can cause a double nat. 

What is Double NAT? | Answer | NETGEAR Support

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