Getting error "the specified gateway ip address is not valid" when trying to set up a static route on Linksys mesh router

Question

I'm trying to set up a static route on a Linksys mesh router (WHWO3V2) and either I don't understand what I'm doing (possible), or the validation script is bad/wrong. I'm trying to do this because I believe (I could be wrong) that this is the only way that I can map a network printer located in the wireless network onto my PC on my wired network.

Network Details: The LAN (wired) IP space is 172.16.20.x The LAN IP gateway is 172.16.20.1

The Wifi router's IP is 172.16.20.2 The Wifi's internal IP space is 172.16.21.x

The static route should be (if I understand it)

• Destination IP address 172.16.20.0 (no errors here)
• Subnet Mask: 255.255.255.0 (no errors here)
• Gateway: 172.16.20.1 (error: the specified gateway IP address is not valid)
• Interface: LAN/Wireless

However, as you can see from the 2nd picture, there is a JavaScript pop up that gives me the error "The specified gateway IP address is not valid". There doesn't seem to be any computation happening to generate this error as there is no lag when I hit "save" (hidden behind the error) and the error.

What I've tried:

• Using 172.16.20.1 as the Destination IP addressed
• Using 172.16.20.2 as the Gateway
• Combinations of both things above
• Trying to pass the error by typing various IP addresses such as 127.0.0.1, 0.0.0.0, 8.8.8.8, and many random IP addresses in the 172.16.20.x IP range.

This shouldn't be this hard, so something is definitely wrong, and that something is likely my understanding of networking. I chatted with Linksys tech support and they were unable to help. Level 2 tech support will call me back within 48 hours.

Answer 1

So while trying just about everything, I stumbled upon a small detail in the Help tab. It stated that:

Since I was using my PC on 172.16.20.x to configure the router, it dawned on me that as far as the Linksys software was concerned, that I was on an external network. This is why I couldn't see so many settings that so many different help websites were showing.

I took a laptop that was connected to the 172.16.21.x network and navigated to the gateway address 172.16.21.1 and behold, I was able to log in to the router AND change the "Type of Internet" setting from DHCP to Bridge mode. The router did its thing for a minute and now all my network devices share the same IP space.

I didn't realize that the "Edit" Type of Internet was not displayed because I was on the different IP space. I thought that I had to make the mesh work with the configuration given. Logging in to the mesh router from the mesh network gave the me options I needed.

SOLVED!