YazFi Some devices can't connect to guest 5GHz after upgrading to Merlin 3004.388.9 on AX86U

[adri]

I'm a big fan of all the work people in this forum have done, my network has been humming away for most of the past 5 years. But today I upgraded to the latest Merlin 3004.388.9 firmware update on my AX86U and things went south. When it came back up:

• many of my devices (Amazon Echos, IP cameras, some smart home devices) can no longer connect to 5GHz guest WiFi - they see the SSIDs but time out trying to connect
• those same devices can connect to my main 5Ghz SSID
• some devices (phones, laptops, desktops) can connect to the 5GHz guest SSs
• I hadn't changed any settings before upgrading
• I'm not seeing anything in the syslog when the problem devices try to connect
• I tried rebooting the router and the devices multiple times, removing and re-adding the network to the devices, and changing the SSIDs
• I tried uninstalling YazFi and connecting, with no luck. Reinstalling did not fix the problem either.

Idk if this is a YazFi issue, a Merlin issue, or a PEBKAC issue (PEBKAC seems likely since I've never really had problems like this with Merlin's firmware). I really, really don't want to do a factory reset (although in the 6+ hours I've spent trying to figure this out so far, I probably could have fully reconfigured the router).

It seems like it must be a 5Ghz radio issue, I changed a few settings (marked below with *) to recommendations I found here, to no effect. Please let me know if anything stands out:

General:
Enable Smart Connect Off*
Band 5 GHz
Network Name (SSID) spiderweb
Hide SSID No
Wireless Mode Auto
802.11ax / WiFi 6 mode Enable
WiFi Agile Multiband Enable*
Target Wake Time Enable*
Channel bandwidth 160 MHz*; Enable 160 MHz checked
Control Channel 36*
Extension Channel Auto
Authentication Method WPA2/WPA3-Personal
WPA Encryption AES
WPA Pre-Shared Key Very Strong
Protected Management Frames Capable
Group Key Rotation Interval 3600

Professional:
Band 5 GHz
Enable Radio Yes
Enable wireless scheduler No
Set AP Isolated No
Roaming assistant Disable
Enable IGMP Snooping Enable
Multicast Rate(Mbps) Auto
AMPDU RTS Enable
RTS Threshold 2347
DTIM Interval 3*
Beacon Interval 100
Enable TX Bursting Enable
Enable WMM Enable
Enable WMM No-Acknowledgement Disable
Enable WMM APSD Enable
Optimize AMPDU aggregation Disable
Modulation Scheme (WiFi 5) Up to MCS 11 (NitroQAM/1024-QAM)
Airtime Fairness Disable*
Multi-User MIMO Disable*
OFDMA/802.11ax MU-MIMO DL/UL OFDMA + MU-MIMO*
802.11ax/ac Beamforming Enable
Universal Beamforming Disable*
Tx power adjustment Performance

I have the full YazFi diagnostic dump and can post it here if the settings above look ok. Nothing obvious popped out at me when I looked at it, but it's entirely possible I missed something.

Thank you in advance for any help!

~ Adriana

 

[adri]

Also, switching the authn method to WPA2-pesonal did not help, nor did enabling Smart Connect.

 

[Kingp1n]

By any chance do you have DFS channels option checked under the Wireless-General tab? If so try uncheck it and try to connect to 5G again. If it works again you can enable DFS again but you might to change the control channel if it keeps disconnecting on '36' while set to Auto.

 

[adri]

I don't think I do, that option disappears when I manually set a control channel. If I look at Systemj Log -> Wireless Log, it says "DFS State: PRE-ISM Channel Availability Check (CAC)" (and then " In-Service Monitoring (ISM)") when I set a 160MHz channel width, or "Idle" when I set it to 80MHz or disable 160MHz. A few more devices can connect when I change the channel width to anything besides 160, but still not all of them.

 

[Apul]

It's an dnsmasq issue. Adguard home is also suffering from this issue

 

[adri]

I tried downgrading to 388.8_4 and still the same issue. Could it really be dnsmasq if the devices aren't even able to authenticate with wifi? They don't seem to get to the stage of making a DHCP request. Regardless, I'm gonna switch the important devices over to 2.4GHz for now, I guess.

 

[Apul]

When I was downgrading to 8_4 my guest was working again

 

[bennor]

• I tried uninstalling YazFi and connecting, with no luck. Reinstalling did not fix the problem either.

What version of YazFi are you running?
When uninstalling YazFI you may need to go in and manually remove, using SSH (PUtty, WinSCP, etc.), the YazFi remnants that don't get deleted by an uninstall. Check the various directories in the /JFFS/ folder for any YazFi leftovers. Reboot the router after fully uninstalling YazFi.

You might need to update to the YazFi Develop version (YazFi 4.4.5).

/jffs/scripts/YazFi develop
/jffs/scripts/YazFi forceupdate

At the end of the day, sometimes strange issues are only fixed/resolved by performing a hard factory reset and manual reconfiguration (do not import a saved router.cfg file). Many times a hard factory reset and manual reconfiguration is faster than spending hours trying to figure out and troubleshoot the strange issue(s) one is experiencing.

Edit to add: And try the usual troubleshooting steps if you haven't done so already.
Avoid using special characters in SSID's and WiFi passwords as a test.
Test with short SSID's and passwords.
If possible instruct the wireless client device to forget all prior saved WiFi connections.
Reset the WiFi client device and try to connect it to the YazFi guest WiFi network.
Doublecheck all YazFi settings including DNS entries if any to ensure they're valid.
Make sure to use unique IP addresses in YazFi.
On some Asus routers the 1st Guest Network is treated differently (for AiMesh) than networks 2 and 3, try using Guest Network 2 and 3 rather than the first Guest Network.
If you have any YazFi custom firewall scripting or YazFi manual WiFi client IP address reservations, remove those scripts/reservations reboot the router.
And as a reminder YazFi does not work on AiMesh or AP nodes, it is main router only.

 

[jrichard326]

Protected Management Frames enabled caused big problems here. Most clients could not connect. When I disabled it, all was well.