Unifi and clients falling back to WiFi4

[chazzy2501]

TLDR: The features in one SSID may affect the underlying radio broadcasts and impact all SSID's 

 

I've been slowly upgrading to Intel AX210's Wi-Fi cards in my laptops (a 6Ghz 6e card) I'd noticed that some clients were using WiFi4 5ghz or 2.4Ghz.  It would seem that bands steering, BSS Transition (802.11v), broadcast filtering and Client Isolation (not so much) being mis-matched across your SSIDs can create issues.  The intel cards are sensitive to this mis-matches in the radio part and will fall back to safe mode. 

 

across my SSIDs (Native and Guests) I've disabled Band steering and BSS Transition I've left auto filtering and client isolation for my guest networks.. This has fixed most of the clients falling back to Wi-Fi4.

 

Things I did try: I did Driver updates, used different Wi-Fi cards APs! I did disable these features 1 by 1 but only on the native SSID at first.  I'd see a lot of DHCP timeouts but only on Wi-Fi and never in the same locations. 

 

Apparently the broadcast filtering (on any SSID but same radio) can delay DHCP enough to bork association cause retries and fail safe fallbacks.  (SO 6 to 4 instead of 6 5 4) ((Chatbot explanation))

 

The chat bot says it may be a quirk of the AX210 with the newer WiFi7 APs. that has brought these issues forward. (A lot of legacy settings and mismatches over the years) I also had beacon intervals set to 3600 on 2 guest networks?! 

 

Still The only clients on Wi-Fi4 now are using older cards on 2.4ghz or older APs.. (Wi-Fi5 is only a 5ghz tech and the U6lite has a Wifi4 2.4Ghz!)