ASUS RT-AC88U running AsusWrt-Merlin 2.4 GHz Guest networks not working

[Ronald Sutton]

I've had this router since 2015 and run AsusWrt-Merlin the entire time. It's running the latest firmware (384.19).

I've had an IoT device connected to one of my 2.4 GHz guest SSIDs for over a year. On December 19, 2019 I checked its logs and saw that it lost its connection and cannot restore it.

While troubleshooting I used multiple devices to scan for WiFi networks and none of them see the three 2.4GHz guest networks that should be visible. SSID hiding is disabled on all 3. I've scanned while sitting in another room and right next to the router. All the devices tested connect to my non-guest 2.4 GHz SSID, so the radio has not failed or been turned off.

When I manually configure one of the guest networks on my phone or tablet and try to connect, they tell me that the network is out of range.

The 5.0 GHz guest networks are working fine, but that doesn't help with my IoT device because its radio only works at 2.4 GHz.

I searched but can't find anyone else reporting the same problem. Any thoughts about what the issue may be?

 

[ColinTaylor]

So you've had this problem since December last year?

Try turning off the MAC filter.

 

[Ronald Sutton]

Thanks for the suggestion. I tried setting the MAC filter to disabled, even though I believe in 'Reject' mode it just rejects the listed MACs. No joy though.

I have another RT-AC88U configured as an access point on the other side of the house. My IoT device connects to it, so I have a workaround but I'd still like to get to the bottom of this.

 

[ColinTaylor]

I have another RT-AC88U configured as an access point on the other side of the house.

Does this other RT-AC88U exhibit the same problem as the first?

When was the last time you did a factory reset on the problem router? Maybe time to do a hard reset.

 

[Ronald Sutton]

As I said, my IoT device connects to my other router just fine.

I compared the 2.4 GHz radio Pro Settings on the two routers and found minor differences, so I changed the first to match those on the second (the one that my device connects to). Still doesn't work.

I don't routinely do factory resets on any device. Do you have a specific fix in mind that can only be accomplished via factory reset?

 

[ColinTaylor]

I don't routinely do factory resets on any device. Do you have a specific fix in mind that can only be accomplished via factory reset?

Not particularly. I'm just wondering whether some nvram settings got corrupted in the past when you did an upgrade. As RMerlin says in the installation instructions,

If something looks weird, don't waste too much time: save your settings, reset to factory default, reconfigure the basics, and see if the issue is resolved. If not, you can always restore your saved settings and do some more advanced troubleshooting.

 

[Ronald Sutton]

Fair enough.

Although my IoT device stopped working months ago, it's a toy so I set it aside until I had more time. Just picked it up again last night, and since I have a workaround it's not urgent.

If I don't come up with any other ideas I may do just as you suggest.

Thanks again.

 

[Ronald Sutton]

Just recalled that I'm using the 2.4 GHz radio on my "first router" (the one exhibiting the problem) to connect a wireless bridge in my family room. I wondered if that could contribute to the problem so I disabled it and rebooted but it didn't fix anything. I still cannot connect to my 2.4 GHz guest SSIDs.

 

[jackz]

I have a similar issue with two RT-AX58U, both running the latest Merlin 384.19 firmware, AiMesh setup with ethernet backhaul. On the regular WiFi, both 2.4 and 5GHz work fine. 5GHz guest networks work fine too but 2.4GHz ones simply won't show up on any device although the SSID should be broadcastet. Even if configured manually, devices cannot connect to the 2.4GHz guest networks. I'd love to have a solution for this so any input would be greatly appreciated!

PS: Strangely, I'm sure that the 2.4GHz guest wifi WAS working ok when I originally set up the routers around a month ago but it appears to have ceased working at some point.

PS2: I also have the impression that even the 5GHZ guest network doesn't work on the mesh node, only on the main router. Are guest networks supposed to work on the mesh nodes?

 

[Qutrit]

Hello! I'm experiencing exactly the same problem with my (only one) RT-AX88U. When I turn on guest network 2.4Ghz my main 2.4 network drops and doens't show up again. Did you solve the problem somehow?