Can't seem to use 5GHz APs with Intel wireless

[Dhananjay Balan]

On Sat, Jun 02, 2018 at 12:37:12AM +0200, Christoph Moench-Tegeder wrote:
> Did you try adding "mode 11a" to select 5GHz band? (This might be
> out-of-date, as my WiFi stuff is all on 11) (currently I'm also
> using 2.4GHz only, for compatibility with some devices and the fact
> that I have quite some trouble running 2.4GHz and 5GHz from the same
> interface at the same time).

I did a bit more testing, I have to admit that I am not well versed in wifi internals.

1. ifconfig wlan0 list aps shows my aps having rate 54M (Im not entirely sure what this means).
   But however when I connect to it, it shows up as 11g

wlan0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
        ether a4:4e:31:02:70:3c
        inet 192.168.23.111 netmask 0xffffff00 broadcast 192.168.23.255
        nd6 options=29<PERFORMNUD,IFDISABLED,AUTO_LINKLOCAL>
        media: IEEE 802.11 Wireless Ethernet MCS mode 11ng
        status: associated
        ssid LA03 channel 6 (2437 MHz 11g ht/20) bssid 52:d9:e7:47:c0:c2
        regdomain FCC4 country DE authmode WPA2/802.11i privacy ON
        deftxkey UNDEF AES-CCM 2:128-bit txpower 30 bmiss 10 scanvalid 60
        protmode CTS ampdulimit 64k ampdudensity 8 -amsdutx amsdurx shortgi
        -stbc -ldpc wme roaming MANUAL
        groups: wlan

2. Adding mode 11a to rc.conf didn't change anything. Still connects to 2.4Ghz band.

3. ifconfing wlan0 scan still doesn't show my 5Ghz only APs (at least some I tested)

Also, what does 11a mean? shouldn't it be 11n?
-
dbalan