I bought GL-AX1800 Flint router few days ago. Before I was using Netgear Nighthawk RAX45 router. And I have Netgear CM1100 cable modem.
Modem has IP of 192.168.100.1. Netgear router had IP of 192.168.1.1. Flint had IP from the factory
set to 192.168.8.1, but I changed it to 192.168.1.1 (as Netgear router was).
When I had Netgear router I was able to log into my Netgear modem with my PC connected to router. But with Flint I cannot get to the modem at all. I get the message: “This site can’t be reached”
Moden Net, 192.168.100.0/24 (maybe a other subnet)
All clients in 192.168.100.0/24 can access 192.168.100.1 as gateway. The Flint WAN port is a client in the Modem Net.
All devices will connect to the Flint LAN Port or WLAN. As router, the Flint will forward all requests outside his net to the gateway.
At first check your client. Open a terminal or command line and type route -n for Windows or ip -r for a recent Linux.
There should be a default route, that points to 192.168.1.1 (Flint). There should be no route for 192.168.100.x (Modem Net).
Than take a look at the Flint. At the start page (Internet?) should be the connection ‘Ethernet’ and there is a IP. This should be an IP 192.168.100.x (X is anything but 0 [net], 1 [modem] or 255 [broadcast]).
All clients from Flint should see all devices in Modem Net without further configuration.
As FYI, here’s some more detail on what’s happening:
TL/DR, modem doesn’t play nice with configuring a 192.168.0.0/24 subnet on the router (netmask of 255.255.0.0).
Just ran into the same problem and narrowed down to a netmask of 255.255.192.0 to scope the range of IPs for the router to:
192.168.0.1 to 192.168.64.255
That leaves 192.168.100.1 squarely outside what the router is managing.
