Iw: resource is bussy(-16) always

Installing and Using OpenWrt Network and Wireless Configuration
1

I need to set a specific Wi-Fi channel using iw-util(it is necessary evade a uci/luci).
I've downloaded basic firmware for my router(Linksys C1900WRT v1.0) from firmware selector and trying to set a specific channel and bandwidth value with this:
root@OpenWrt:~# iw dev phy0-ap0 set channel 11 HT20
And every time I get this error:
command failed: Resource busy (-16)
With searching the Internet I've found out, that for some reason my AP scans networks every 0.1s. My assumption is based on output of this command:
watch -n 0 iw wlan0 scan

The only way I can to execute this iw dev phy0-ap0 set channel 11 HT20 without finding out an error is putting the AP's interface down, but for some reason changes are not getting saved then.
SO how can I set a desirable channel and bandwidth?

P.S.: I think some time ago I did it successfully on some x86_64 OpenWRT machine, but now it doesn't work for some reason or I forgot some steps to do.

2

I'm pretty sure you have to first have put the interface down then that command then you have to bring it up

ip link set phy0-ap0 down
iw phy0-ap0.......
ip link set phy0-ap0 up

Your probably better off using UCI commands the command you are using is only temporary and be lost on next reboot or restarting the network

3

I know that UCI is better due to it saves state, but at my case I need to use some other way to setup a channel.

And here's the thing that I can't get, there's nothing changing for some reason:

root@OpenWrt:~# ip l set dev phy0-ap0 down
root@OpenWrt:~# iw dev phy0-ap0 set channel 1
root@OpenWrt:~# ip l set dev phy0-ap0 up
root@OpenWrt:~# iw phy0-ap0 info
Interface phy0-ap0
        ifindex 14
        wdev 0x3
        addr 94:10:3e:98:18:a7
        ssid OpenWrt
        type AP
        wiphy 0
        channel 2 (2417 MHz), width: 20 MHz, center1: 2417 MHz
        txpower 20.00 dBm
        multicast TXQ:
                qsz-byt qsz-pkt flows   drops   marks   overlmt hashcol tx-bytes        tx-packets
                0       0       0       0       0       0       0       0               0
4

You can use hostapd_cli from hostapd-utils to tell hostapd to switch channels.

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