Ubiquity AP AC Pro no 5Ghz on many clients

summerfranks · March 8, 2022, 5:42pm

So I just got a brand-new Ubiquiti UniFi AC Pro to replace my old crap TP-Link 802.11agn router. Install was completely painless. Just set it up as a very basic AP with DHCP client on the LAN port. The problem is a bunch of my 5GHz-capable devices fail to even see the SSID on 5Ghz, it's like it's not on, but several other clients have zero issues. I've tried every possible permutation of channel and spacing/bandwidth (20/40/80), AC mode, N mode, legacy mode, WPA2 & 3, 802.11w enabled & disabled, I'm all out of ideas!

The deets:
OpwnWrt 21.02.2 r16495-bf0c965af0
ath79/generic
Qualcomm Atheros QCA956X ver 1 rev 0

The following devices connect just fine:

Intel 8260 iwlwifi driver
Samsung A12 (android)

The following devices fail to see the SSID:

Intel 6205 iwlwifi driver
Realtek RTL8814AU rtl88XXau driver

The realtek device is advertised specifically as an 802.11ac device, and was purchased within the last 6 monts.

You'll also notice two devices using the iwlwifi driver, the older of which fails, and the newer of which works, so I guess it's not a driver issue. Both are on laptops running the latest Mint 20.03.

So, I'm all out of ideas. The 2.4G is really congested in my location, so I'd really like to get the 5G working on all my devices, they all worked flawlessly with the TP-link router.

Thanks!
Summer

AashishAS · March 8, 2022, 5:55pm

Try using channel 36?

summerfranks · March 8, 2022, 6:43pm

Oh, that was nasty. Some helpful references:

github.com/openwrt/luci

luci 802.11ac wifi channels listed incorrect for width size selected

opened 01:49PM - 07 Jun 18 UTC

closed 04:10PM - 09 Oct 19 UTC

sirjaymz

luci does not update to the correct available channel list when selecting the wi…dth size of the operating frequency for a Qualcomm Atheros QCA9880 802.11nac (Archer C7), and maybe other chipsets as well. These lists are mutually exclusive, meaning, channels identified on 20Mhz width list are not duplicated in other width lists. Same goes with 40Mhz width's are not duplicated, as well as 80Mhz, and the 160Mhz width lists. **When selecting a 20 Mhz width size, the following channels should be listed.** All allowable channels should be listed per regulatory. This list is currently what luci displays for ALL (20, 40, 80) frequency widths, which is incorrect. This is correct for the 20Mhz width size only. [Ch (Mhz)] 36 (5180), 40 (5200), 44 (5220), 48 (5240), 52 (5260), 56 (5280), 60 (5300), 64 (5320), 100 (5500), 104 (5520), 108 (5540), 112 (5560). 116 (5580), 120 (5600), 124 (5620), 128 (5640), 132 (5660), 136 (5680), 140 (5700), 144 (5720), 149 (5745), 153 (5765), 157 (5785), 161 (5805), 165 (5825) **When selecting a 40 Mhz width size, only these channels should be displayed.** 38 (5190), 46 (5230), 54 (5270), 62 (5310), 102 (5510), 110 (5550), 118 (5590), 126 (5630), 134 (5670), 142 (5710), 151 (5755), 159 (5795) **When selecting a 80 Mhz width size, only these channels should be displayed.** 42 (5210), 58 (5290), 106 (5530), 122 (5610), 138 (5690), 155 (5775) **When selecting a 160 Mhz width size, only these channels should be displayed.** Not sure if this needs to be included, as the Archer C7 does not support 80+80 or 160 frequency widths but, other chipsets may support it, so maybe beneficial to fix it in luci anyway. 50 (5250) 114 (5570) The list should be updated, dependent upon which country the user has selected as the Regulatory body and laws require. As an example, New Zealand and the USA follow literally an identical frequency range, [here is an example](https://web.archive.org/web/20170802164314/https://www.rsm.govt.nz/consumers/pdf-and-documents-library/Wi-Fi%20Devices%20using%20the%205%20GHz%20Band.pdf) of how the frequencies and the overlaps are rolled up and visually identifiable. Reference : [List of WLAN channels](https://en.wikipedia.org/wiki/List_of_WLAN_channels#5_GHz_(802.11a/h/j/n/ac/ax))

So it would seem Luci uses the lowest 20MHz channel as the number, because 36 & 100 both seem to work @ 40 & 80MHz. 36 is hopelessly congested in most populated areas, I don't recommend it.

Problem #2, no permutation of WPA3 settings would allow connect on all my systems. However WPA2 is just fine.

anon89577378 · March 8, 2022, 7:00pm

WPA3 needs to be supported on the clients as well.

mk24 · March 8, 2022, 7:12pm

Make sure your correct country code is set on both radios. With the country unset, you get reduced wifi performance because it can only use the restricted frequencies and modes that would be legal anywhere.

summerfranks · March 8, 2022, 7:15pm

Sage words my friend, glad you could add to the conversation along side AashishAS.

I would add that all the warring systems are current linux distros. And the main hangup appears to be some need 802.11w to be set to "required" and others to "disabled". As it mentions right below the setting, some drivers & hardware choke on 802.11w hard (not sure why some won't connect without it though, but who am I). So, in other words, WPA3 isn't really mature, I recommend anyone who reads this post just go with WPA2 only and move on with their lives, which is why I brought it up in the first place.

summerfranks · March 8, 2022, 7:25pm

If reality follows the second link I posted, channels 52 & 116 are also solid choices, although I haven't gotten a chance to try them as 100 appears to fit my needs. I can confirm that 149 which appears to be a valid choice from the table did not, in fact, work.

anon89577378 · March 8, 2022, 7:28pm

Or, you could find out what devices you have that support WPA3, and set up a separate guest/IoT WiFi network for those only.

anon89577378 · March 8, 2022, 7:37pm

In most geographic locations, 52 and 116 are DFS (radar) channels, and should be avoided.

Select a channel in the range 36 to 48, or 149 to 161.

summerfranks · March 8, 2022, 8:16pm

Could they make the next 802.11 standard bloody channel hop already? The level of esoteria is getting obscene lol

AashishAS · June 9, 2022, 4:54pm

149 is the sweet spot, not congested and widely available. Try setting your driver country to India, this can help make channel 149 work for testing purposes.