OpenWrt Split Tunnel WireGuard Omada Double NAT
I have been thrown into a unique network setup and could use some help. My network design started out with an Omada system (Router, Switch, EAPs) but I also need to incorporate a router to connect to our VPN service. I've been doing this with a Linksys 3200ACM running OpenWRT and a Wireguard interface. My network topology looks like the following:
ISP -> (WAN Port) OpenWRT Router (192.168.1.1) running WireGuard -> (WAN Port) TP-Link Omada Setup (ER605 192.168.0.1) (Managed Switch) and (EAPs)
This works but I want the ability to do split tunneling via VPN and WAN Policy-Based Routing. The way to do this is usually by identifying the IP address you want to run through the WAN instead of the VPN. All my IPs are behind the Omada system of 192.168.0.1 with several VLAN subnets. These IPs of course are not being seen by the OpenWRT router and no policy will work on them.
One thought I had was cascading the two routers and wanted some input on whether this would even work or the best way to do it. Thanks.
What if I were to cascade my routers in the below fashion? Would it allow the IPs to be seen by OpenWRT? I think the only way for it to work would to turn off DHCP on the OpenWRT to allow Omada to set the IPs.
ISP -> (WAN port) OpenWRT Router (change IP to 192.168.0.1 turn off DHCP) running WireGuard -> (LAN port) TP-Link Omada Setup with VLANS i.e.(main Omada router 192.168.0.2/24), 192.168.2.X, 192.168.3.X (ER605) (Managed Switch) and (EAPs)