RT-AX86U (AX5700) router dropping smart home devices every few weeks but Wi-Fi still works

[pandacat]

Been noticing my Asus RT-AX86U Router keeps dropping smart home devices (water sensors, cameras, temperature monitors, appliances). I Googled and this seems to be a known issue.

All my devices are connected to Guest Network (which has a different SSID than Main Network). That Guest Network uses 2.4 GHz. I have tried both "Enable" and "Disable" in the "Access Intranet" Option which made no difference. Time Remaining is "Unlimited access." I have also tried Disabling Roaming Assistant for the 2.4 GHz band.

I'm on the latest stock firmware. Not on AiMesh. Automatic DHCP IPs.

Security level is WPA2-Personal for Guest Network. My smart home devices on this network drops every few weeks and it's only these devices. My Wi-Fi on that same network still works. The only way to have the smart devices reconnect is to turn on and off the router.

Any recommendations?

 

[bennor]

What make/model are the smart home devices that are dropping?
Do these same smart home device drop if they are on the main WiFi network (not the guest network)?
Which Guest Network # are you using? If using Guest Network #1 try using Guest Network #2 instead. The Asus firmware may treat Guest Network #1 slightly differently (due to the AiMesh code in the firmware even when not used) than Guest Network #2 and #3.

A troubleshooting step. Make note of the 2.4Ghz channel number when the smart home devices are working, then make note of the 2.4Ghz channel number when the smart home devices are dropped from the WiFi. Could be the WiFi 2.4Ghz channel has changed an the devices have trouble picking up the new channel. If this is the case, one may have to manually set the 2.4Ghz WiFi channel to one the smart home devices support.

It may help if you post your 2.4Ghz WiFi settings, both General and Professional pages (redacting any sensitive information) in case others see a settings issue.

 

[FredTheFrog]

The only thing (and I just tried it a few days ago) was to set the 2.4GHz band to Legacy mode. All my ESP8266, ESP32, thermostats, and other wireless devices are MUCH happier when the Asus firmware does NOT try to play with N tricks.

 

[pandacat]

Update: My Asus RT-AX86U continues to drop smart home devices at random intervals, sometimes within a day or two, and sometimes every 1-2 weeks. There seems to be no reason on the variable length.

These devices include water and temperature sensors, cameras, lighting controls, thermostat, alarm panels, and appliances.

How I have it set up:

• Main devices like my PC and phone are Connected to Main Network (2.4 GHz and 5 GHz)
• All smart home devices are connected to Guest Network #2 (which has a different SSID than Main Network). That Guest Network uses 2.4 GHz. Automatic DHCP IPs.
• Security level is both WPA2-Personal for Main and Guest Network (different keys).
• Time remaining is "Unlimited Access."

What I have tried to fix this issue:

• Tried Guest Network #1 and Guest Network #2. No difference.
• Enable and Disable "Access Intranet" on Guest Network #2. No difference.
• Disabled Smart Connect Rule.
• Also tried Disabling Roaming Assistant for the 2.4 GHz band.
• No difference in using latest stock firmware or Asuswrt-Merlin. Currently on the latest version of Asuswrt-Merlin.

The odd thing is that my Wi-Fi on the Guest network still works yet the smart devices keep disconnecting. I am intrigued to why this is.

The only way to have the smart devices reconnect is to turn on and off the router. Any recommendations?

Also note that I do not have this issue at another residence location using the same router model and similar smart home devices running on a guest network. Because of this, I'm wondering if it is my particular router that has issues.

 

[OzarkEdge]

Have an Asus RT-AX86U Router where it keeps dropping smart home devices at random intervals, sometimes within a day or two, and sometimes every 1-2 weeks. These devices include water and temperature sensors, cameras, lighting controls, thermostat, alarm panels, and appliances.

How I have it set up:

• Main devices like my PC and phone are Connected to Main Network (2.4 GHz and 5 GHz)
• All smart home devices are connected to Guest Network #2 (which has a different SSID than Main Network). That Guest Network uses 2.4 GHz. Automatic DHCP IPs.
• Security level is both WPA2-Personal for Main and Guest Network (different keys).
• Time remaining is "Unlimited Access."

What I have tried to fix this issue:

• Tried Guest Network #1 and Guest Network #2. No difference.
• Enable and Disable "Access Intranet" on Guest Network #2. No difference.
• Disabled Smart Connect Rule.
• Also tried Disabling Roaming Assistant for the 2.4 GHz band.
• No difference in using latest stock firmware or Asuswrt-Merlin. Currently on the latest version of Asuswrt-Merlin.

The odd thing is that my Wi-Fi on the Guest network still works yet the smart devices keep disconnecting. I am intrigued to why this is.

The only way to have the smart devices reconnect is to turn on and off the router. Any recommendations?

Also note that I do not have this issue at another residence location using the same router model and similar smart home devices running on a guest network. Because of this, I'm wondering if it is my particular router that has issues.

I would suspect WiFi settings first before hardware... try tweaking the 2.4 WLAN... fix 20MHz bandwidth to be courteous and to stop the router from switching between 20 and 40 to avoid interference (if happening, can upset clients)... fix the control channel to the one channel that appears to work best... test them all. And disable Universal Beamforming... proprietary and could upset the odd client.

Beware nearby USB3.0 devices generating EMI in the 2.4 band... and similar EMI culprits like cordless peripheral devices and microwave ovens. This interference can upset 2.4 client connections.

OE

 

[bennor]

Have an Asus RT-AX86U Router where it keeps dropping smart home devices at random intervals, sometimes within a day or two, and sometimes every 1-2 weeks.

Have you checked the router system log to see if it indicates any issues or reason why the clients are being disconnected?
Do you have a USB 3.0 device connected to the router's USB port?
As already suggested, could be an issue with your WiFi settings.
It sometimes helps to choose a specific WiFi channel rather than leave it set to auto.

 

[Ripshod]

Just to add, I suggest lifting "Group Key Rotation Interval" to 86400 (24 hrs).