Question RT-AC86U AiMesh wireless issue

Barney88

Prominent
Jul 14, 2021
12
2
515
Hello everyone.
I have 2 AC86U routers in AiMesh. The main router is on the ground floor and the node is on the first floor with ethernet backhaul mode. There are 25 devices connected to the network, of which 15 are wireless (home appliances with no LAN connection: smart lights, doorbells, etc.. ). Both routers are using the latest FW (3.0.0.4.386_48260), separate SSIDs for 2.4 and 5Ghz WiFi, and smart connect is turned off. The rest of the settings are on default. Sincerely I'm using the system for half a year already but almost every week the main router drops all the WiFi connections, and the devices reconnect to the node (reboot solves the issue). In this situation, the farthest devices receive just minimal signal and randomly appear offline. This issue happens only with WiFi devices, the cabled devices stay connected always. Tried binding the devices to the main router, but in this situation when the WiFi drops they do not reconnect to the node either. Performed hard/factory reset multiple times. Tried switching up the 2 routers or placing them further from each other. Nothing helped. After a couple of days, the main router just disconnects all the wireless devices. I even tried it in Router-AP mode, and the same thing happens. Before I used 2 TPlink Archer C7 in Router-AP mode and I didn't face this issue. I have no idea what else I could try, and I really hope that someone here can help me.
 
It would be really nice if these devices had more logging information. Unfortunately all this type of information is locked up in the wifi radio chipset and even the router manufactures can't see it unless the wifi chipset maker chooses to send these to the router chip.

Do you know if you lose both the 2.4 and 5g radios. Could be a hardware issue but then it shouldn't do the same thing if you swap them.

If it was something more basic like the router crashing your wired connections would also be affected.

The easier way to force devices to connect where you want would be to use different SSID on the the main and remote routers. They should only connect to the one you configure being sure the device does not have the other one also configured. This would prevent them from switching unless you manually forced it to switch.

Not sure it could be related to the mesh software. I really hate that stuff. The end device not the network is responsible for where it is connected. Since these mesh systems can't actually tell a end device where to connect what they sometime do is force a device off the network and hope it connects to a better source.
If it is possible I would disable any mesh abilities and run the units as a simple router and remote AP.
 

Barney88

Prominent
Jul 14, 2021
12
2
515
It would be really nice if these devices had more logging information. Unfortunately all this type of information is locked up in the wifi radio chipset and even the router manufactures can't see it unless the wifi chipset maker chooses to send these to the router chip.

Do you know if you lose both the 2.4 and 5g radios. Could be a hardware issue but then it shouldn't do the same thing if you swap them.

If it was something more basic like the router crashing your wired connections would also be affected.

The easier way to force devices to connect where you want would be to use different SSID on the the main and remote routers. They should only connect to the one you configure being sure the device does not have the other one also configured. This would prevent them from switching unless you manually forced it to switch.

Not sure it could be related to the mesh software. I really hate that stuff. The end device not the network is responsible for where it is connected. Since these mesh systems can't actually tell a end device where to connect what they sometime do is force a device off the network and hope it connects to a better source.
If it is possible I would disable any mesh abilities and run the units as a simple router and remote AP.

Thanks for the fast reply. The answer to your question is yes, I do lose both 2.4 and 5g radios and the connected devices reconnect to the node. The strange thing is that the same issue happens in router AP mode also but less frequently. It is always the main router witch drops the connection. At first, I suspected also faulty hardware and the store replaced the device with a new one, but since then I also swapped the router and the node with no help...
 
This is where it would be nice to know if the signal actually does away or if it is disconnecting at some software thing...ie the router is sending out a disassociate all frame. This used to be a common attack you could do against someone you didn't like by spoofing that messages but the latest forms of wifi have fixed that hole.
The router itself though can still send that message.

This is differnet than if the wifi radio itself just turns off and stops transmitting. I am not sure how you can tell though.

Do you still have one of the archer devices maybe you could use that as a AP that just happens to sit next to the main router and not use the main routers wifi. Not the best option but wifi leaves you almost no options. You load the firmware and hope the chips work. You can set things like passwords and channel numbers but little else.
 

Barney88

Prominent
Jul 14, 2021
12
2
515
This is where it would be nice to know if the signal actually does away or if it is disconnecting at some software thing...ie the router is sending out a disassociate all frame. This used to be a common attack you could do against someone you didn't like by spoofing that messages but the latest forms of wifi have fixed that hole.
The router itself though can still send that message.

This is differnet than if the wifi radio itself just turns off and stops transmitting. I am not sure how you can tell though.

Do you still have one of the archer devices maybe you could use that as a AP that just happens to sit next to the main router and not use the main routers wifi. Not the best option but wifi leaves you almost no options. You load the firmware and hope the chips work. You can set things like passwords and channel numbers but little else.

Unfortunately, I do not have the old routers anymore. But I was thinking that I will buy 2 new TPlink routers and never deal with ASUS anymore...
 
Not sure the wifi function is some bin file you load into the radio chip.

When I first was looking at third party firmware I had all kinds of ideas but after looking at the source code all the fun stuff is locked away in the radio chips where you have no access to the actual code. All I was hoping to do was add a display that showed how many packets were being re transmitted but all the data in not available.
 

Barney88

Prominent
Jul 14, 2021
12
2
515
Now I tried to change the Tx power adjustment to balanced and to set the channels manually (unused channels, different from the neighbors, etc...) but it didn't help. Never had issues with the ISP/WAN signal, every time when the wifi drops on the main router, I still have internet on the node and on the LAN connections. But as strange as it sounds if I walk out from the covered area with my phone (my phone disconnects from the wifi network completely) and reenter, after reentering it reconnects to the main router normally if nothing happened (the same if I restart all the disconnected appliances). I have had no issues with the backhaul mode. The node always stays connected and there is always internet from it. And another strange thing is that the WEB interface and the APP are showing the connections differently (like on the WEB interface my doorbell is connected to the main router and the APP shows that it's connected to the node)...i am really confused
 

Barney88

Prominent
Jul 14, 2021
12
2
515
I tried also with only one router to see what is going to happen. And after 2 days of working the router lost all the connections (wireless and wired). I couldn't even connect to the router interface. Only a power reset helped. There were no red LEDs on the router, all of them were white. The issue happened on 10.11.2022 at 06:40 when all my devices disconnected. The log file starts at 06:50 (https://pastebin.com/EfG7wKmS) and I have no idea what happened with the logs before that time. I restarted the router at 07:09. Maybe someone can find out something from the log between 06:50-07:09...
 
It would be very nice if they would document what those messages mean. I have not gone to the effort to try to look at the source code (most asus devices use a open source version of firmware). I doubt it says much these messages appear to be coming from the wifi chip but the router is calling them "eth5".

Have you tried the merlin firmware to see if it runs any different this could be some kind of bug in asus firmware.

I am somewhat surprised the log survived a power cycle. Most times the log is kept in normal ram that is cleared on a power cycle, they must be keeping it in some kind of flash now