I'm trying to exclude the use of the 6Mbit wireless rate on my network.

My config section looks like this:

config wifi-device 'radio0'
        option type 'mac80211'
        option hwmode '11a'
        option path 'pci0000:01/0000:01:00.0'
        option txpower '17'
        option country 'US'
        option disassoc_low_ack '0'
        option channel '149'
        list basic_rate '12000 18000 24000 36000 48000 54000'
        option htmode 'VHT80'

In /var/run/hostapd-phy0 I see

basic_rates=120 180 240 360 480 540

But when I sniff the RF layer with host I still see the AP transmitting 6Mbit packets.

Is there something else I need to do to remove 6Mbit from the list of possible rates?

This is on a Archer C7 v2 (ath10k) running CC 15.04rc2

Why did you use "list basic_rate" and not "option basic_rate" ?

From the info I found here:

https://forum.openwrt.org/viewtopic.php?id=56546

I've confirmed it works because the following config line:

list basic_rate '24000 36000 48000 54000'

Results in this showing up in /var/run/hostapd-phy0.conf

basic_rates=240 360 480 540

Did you ever find the solution?
Seeing same behaviour in my setup.

Hostapd on AP

hw_mode=g
basic_rates=540
channel=01

iwlist scan on the Ubuntu machine

Encryption key:on
                    ESSID:"2-test"
                    Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 11 Mb/s; 6 Mb/s
                              9 Mb/s; 12 Mb/s; 18 Mb/s
                    Bit Rates:24 Mb/s; 36 Mb/s; 48 Mb/s; 54 Mb/s

(Last edited by Shogo on 3 Feb 2016, 13:01)

Unfortunately,  I did not.   I've had to put figuring it out on the TODO list and work on other things.

Try supported_rates. Basic rates are used for the frame preamble, not the data.

(Last edited by eas on 4 Apr 2016, 07:55)

This forum post explains why bitrates are still seen even when "basic_rate" is used:
https://forum.openwrt.org/viewtopic.php?id=56546

Also a good resource - https://dev.openwrt.org/ticket/18627

I have tried:
list supported_rates '12000 18000 24000 36000 48000 54000'
list basic_rate '12000 24000 54000'

And on TPLINK WDR4300 running CC 15.04.01
on 2.4Ggz interface: Bit Rates:12 Mb/s; 18 Mb/s; 24 Mb/s; 36 Mb/s; 48 Mb/s; 54 Mb/s
but 5.8 Ghz interface: Bit Rates:6 Mb/s; 9 Mb/s; 12 Mb/s; 18 Mb/s; 24 Mb/s; 36 Mb/s; 48 Mb/s; 54 Mb/s