Business gateway - NAT to IP Address on local LAN

[jreedtbf]

Im having a lot of trouble setting up a NAT statement on my Netgear modem.   

My modem IP is 10.1.1.1 and is connected to 10.1.1.2 on my firewall.  Behind the firewall I have a LAN or 192.168.1.X.  I am trying to NAT one of my static IPs from Comcast to a server on the 192.168.1.X network.   When I do add this via 1 to 1 NAT, I get the message Status: Invalid IP Address.

I had to get a new modem today and havent been able to get this working.  With my previous modem, it worked.

[Comcast_Gabe]

Hi! Thanks for reaching out. I can help with the internet service concern. Would you mind sending a private message with your full name, the last four digits of your account number, and a phone number linked to the account so I can help?

[jreedtbf]

Information sent.   

I also called Comcast support but they werent able to help.

It seems the problem is NAT'ing to an address on a different subnet.   I have a route setup to that subnet but that doesnt help.   I'm not sure why this worked before on the SMC modem.    Is there a different mode or feature that needs enabled?

[jreedtbf]

 

This is the configuration of my IP's from my old modem that was working.

[CC-Michelle1]

Jeremy, thank you for all of the information. I am happy to assist with the modem settings. Can you please confirm the address on the account? Can you tell me what the firewall settings are at on the modem? 

[jreedtbf]

Just sent you a private message.