RT-AX88U: wireless router mode: Cannot connect from LAN or WI-FI

[Anno.Me.Nuehm]

Just recently I have obtained an ASUS RT-AX88U wireless router, with the intend to added as a router to my already existing LAN, accepting connections from both wireless as well as wired clients.

The specific setup would be as depicted below.

   { internet }
    |
<dsl modem>
    |
[firewall #1]
    |
   (dmz)
    |
[firewall #2]
    |
   (lan #1)
    |
[rt-ax88u] — (wi-fi)
    |
   (lan #2)

The WAN port of the ASUS is connected to one of the LAN ports of firewall #2, thus segregating my LAN into lan #1, lan #2, and wi-fi.

Setting up the ASUS as an AP (LAN ports are not operating) works perfectly fine, albeit when choosing router mode I can reach lan #1 and the internet directly from within ASUSwrt (logging into the ASUS, and facilitating any of the network tools there, leads to success.), but not a single device connected to the ASUS (lan #2, wi-fi) can get through at all!

I have added the following static routes:

(1) ASUS LAN -> ASUS WAN (192.168.50.0 / 255.255.255.0 -> 192.168.5.2; 1 hop; lan); --and--
(2) ASUS WAN -> ASUS LAN (192.168.5.2 / 255.255.255.0 -> 192.168.50.1; 1 hop; wan);

but still no avail.

If I would not need getting the LAN ports up & running on the ASUS, I would stick with the AP mode, but unfortunately this is not an option.

Any hints as how to tackle this one would be more than appreciated.

 

[ColinTaylor]

If I would not need getting the LAN ports up & running on the ASUS, I would stick with the AP mode, but unfortunately this is not an option.

All the LAN ports should work fine when the Asus in AP mode.

 

[Tech9]

In router mode LAN2 can access LAN1, but not the other way around. The router should have no issues serving both wired and wireless clients. Static routes are not needed. Router’s firewall prevents LAN1 devices to access LAN2. Is this the goal? What’s the situation with the 2 firewalls with one of them in DMZ? What is Firewall 1 doing on this network?

 

[Anno.Me.Nuehm]

All the devices are located in a SOHO environment. Inside the DMZ--that is in between flod/firewall #1 and slod/firewall #2, there are the storefronts of some publicly accessible web services operated.

The ASUS router is solely to be found within the LAN environment, and if there should be any firewall configured on this router, then purely protecting the LAN from any device connected to the wi-fi.

 

[ColinTaylor]

All the devices are located in a SOHO environment. Inside the DMZ--that is in between flod/firewall #1 and slod/firewall #2, there are the storefronts of some publicly accessible web services operated.

The ASUS router is solely to be found within the LAN environment, and if there should be any firewall configured on this router, then purely protecting the LAN from any device connected to the wi-fi.

Sorry, I can't understand your setup. Where/what is the router for LAN #1? Where is the DHCP server for LAN #1?

 

[Anno.Me.Nuehm]

Sorry, I can't understand your setup. Where/what is the router for LAN #1? Where is the DHCP server for LAN #1?

slod/firewall #2 has got on the LAN-facing side dns, dhcp & ntp services, as well as it is acting as the gateway router to the dmz, and in the long run to the wan/internet

the asus is intended to extend lan #1 to an additional space in the soho environment, as well as creating a second, separate lan (lan #2).

 

[Anno.Me.Nuehm]

All the LAN ports should work fine when the Asus in AP mode.

I have tried this (again), and it appears as if last time I just failed to be patient enough, because it is taking a couple of seconds up to almost a minute for any device connected to the LAN ports of the ASUS the register appropriately and gain access to the networks beyond the ASUS.

 

[ColinTaylor]

I have tried this (again), and it appears as if last time I just failed to be patient enough, because it is taking a couple of seconds up to almost a minute for any device connected to the LAN ports of the ASUS the register appropriately and gain access to the networks beyond the ASUS.

I can't imagine why that would be, I've never heard of any one else reporting such a thing. In AP mode all the Ethernet sockets should form a single switch so traffic should be getting to your upstream gateway straight away. (Of course it's possible there's a bug in AP mode)

Try replacing the cable connecting the Asus to your upstream network. Also try plugging this cable into a different sockets on the Asus. Are you using Jumbo frames on your LAN? If so this needs to be enabled on the Asus under LAN - Switch Control.

 

[Anno.Me.Nuehm]

I can't imagine why that would be, I've never heard of any one else reporting such a thing. In AP mode all the Ethernet sockets should form a single switch so traffic should be getting to your upstream gateway straight away. (Of course it's possible there's a bug in AP mode)

Try replacing the cable connecting the Asus to your upstream network. Also try plugging this cable into a different sockets on the Asus. Are you using Jumbo frames on your LAN? If so this needs to be enabled on the Asus under LAN - Switch Control.

Thanks for your support!

All is fine now!

 

[ColinTaylor]

Thanks for your support!

All is fine now!

That's good to hear. Did you need to make any changes or did it just sort itself out?

 

[Anno.Me.Nuehm]

That's good to hear. Did you need to make any changes or did it just sort itself out?

I actually just flashed ASUSwrt-Merlin, and restarted the device...