Client (macbook) cannot connect to specific channel (165)

Normally, I have my wifi channel selection set to AUTO, but I have noticed that my macbook laptop sometimes has problems connecting. I did some digging, and found that the problem occurs when the router selects channel 165. I have also tested this by manually selecting channel 165 on the router with the same result. Is there any way to ask LEDE to not use channel 165 while AUTO selecting?

I have reported the problem to Apple, but do not know if it'll be fixed anytime soon. Someone on the apple forums said it might be an incorrect beacon code in my neighborhood, but that would be difficult to track down and do something about...

Are both set to the correct jurisdiction for your country? Every country has there own regulation for wifi channels. Regulation is fairly consistent across the world for 2.4GHz (802.11b/g/n), but it's all over the place for 5GHz (802.11a/n/ac).

For example, some 5GHz channels has Radar Detection requirements in many countries (called "DFS"), so those channels should be disabled when radar is detected. However, the implementation of that varies greatly from devices to device. Some device manufacturers just disable those channels all together.

According to https://en.wikipedia.org/wiki/List_of_WLAN_channels, channel 165 is a SRD channel in Europe. I am not sure what restriction SRD has. Maybe Macbook doesn't support SRD channels, so it's disabled.

Channels 149-165 (ETSI EN 300 440-1) are a relatively recent addition to the allowed spectrum (a good ~year ago), not every OS or drivers knows about that yet. You can restrict the allowed channels of your wifi-device via the channel_list directive.

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@slh Is this the "channels" option on "wifi-device" in /etc/config/wireless mentioned on https://lede-project.org/docs/user-guide/wifi_configuration ? Don't know how I could have missed that, will try as soon as I get home.

BTW, my country code is NO (Norway), which I guess should follow the laws in Europe.

The channels option worked like a charm! I was a little confused how and where it was supposed to be written, but the following entry in /etc/config/wireless did the trick:

config wifi-device 'radio1'
	option type 'mac80211'
	option hwmode '11a'
	option path 'pci0000:00/0000:00:00.0'
	option htmode 'HT20'
	option country 'NO'
	option channel 'auto'
	list channels '36-157'

BTW, will hostapd rerun the channel auto selection at some interval, or just when it starts? I tried to google for the answer but could not find it. I even tried to look at the source code with little success.

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for 2.4GHz in macbook , use at 1 to 11 channels