Second router in home network - how to setup properly

Question

today I got a router to split my home network in two partitions to isolate some devices. In particular I have Raspberry Pi which I would like to access from the internet and keep all my other devices (desktops and stuff) in a separate network. Now I achieved to setup the router, setup the gateway and voilá, I can get online from behind the router. I can't access any device in the new network (I assume the firewall blocks all requests), but I can access all devices in the old network from the new network, which I actually don't want to. To clarify the setup:

• My initial network (192.168.0.XYZ)
• The new network (192.168.1.XYZ)

New network is connected via LAN to the old network and 192.168.1.1's gateway is 192.168.0.1, furthermore 192.168.0.1 has a dynamically assigned IP from my ISP. If I would switch the new router to be the gateway everything works fine (this means switch all the wiring from old to new network), but I don't want that, because my old router has more features and capabilities. How can I achieve that devices on the new network may only talk to the devices in the old network via opened ports (if at all) and vice versa? Thank you for your help.

EDIT:

I plan to put the Pi in the new network (192.168.1.XYZ). Here is what I tried so far:

• Connect the WAN port of the new router to any port of the old router.
• Assign the new router a static WAN IP of 192.168.0.2 (subnet mask is 255.255.255.0), default gateway is 192.168.0.1, primary DNS is 192.168.0.1 as well.

It seems I cannot connect from the new network to the old one anymore. However pinging 192.168.0.2 from the new network works fine, but pinging 192.168.0.1 does not work. I read something about static IP routes - do I have to implement these somewhere? Thank you for your help.

Answer 1

Your networks need to be "reversed."

Presently your new network with your Raspberry Pi is connected to your old network with your other devices, which in turn connects to the Internet.

Instead, you should have your Raspberry Pi (which you want accessible from the Internet) in the network that's the closest to the Internet, and the rest of the devices in the second network. In other words:

Internet---Router 1---(Raspberry Pi)
             |
             +---Router 2---(other devices)

Set up this way:

1. All of your nodes will have access to the Internet
2. A port-forwarding rule on Router 1 will make the Raspberry Pi accessible from the Internet
3. The first network (with the Pi) won't have access to the second network due to Router 2 firewalling that network