RTL8723BU Can't See 5GHZ

[Poincare1]

Hello, I followed the auto DKMS install method and it appears to be installed correctly for the rtl8723bu. However, it is only seeing 2.4ghz access points and not 5Ghz ones.

Is there a method for getting this kernel module to also recognize 802.11n access points on 5ghz?

Thank you.

[lwfinger]

On my system, I get the following:

finger@linux-n6zm:~/rtl8723bu> sudo insmod 8723bu.ko finger@linux-n6zm:~/rtl8723bu> iw dev phy#0 Interface wls1 ifindex 3 wdev 0x1 addr 00:e0:4c:09:94:1d ssid Larry_ac2_5GHz type managed channel 40 (5200 MHz), width: 80 MHz, center1: 5210 MHz txpower 20.00 dBm

Note that the 8723bu is connected to a 5GHz AP, thus the problem is not with the driver.

Run the command 'lsmod | grep 8xxxu'. If you see any output, then you need to unload rtl8xxxu. To prevent future problems, you should blacklist it.

[Poincare1]

Not sure what the issue is. I am not running the 8xxxu module. There is no output from lsmod | grep 8xxxu nor is it listed in the loaded modules. Again, it's not seeing any 5ghz APs. Here is output from iwconfig:

root@rock64:~# iwconfig lo no wireless extensions.

wlx74da38f3cbcc unassociated Nickname:"WIFI@REALTEK" Mode:Managed Frequency=2.412 GHz Access Point: Not-Associated
Sensitivity:0/0
Retry:off RTS thr:off Fragment thr:off Encryption key:off Power Management:off Link Quality=0/100 Signal level=0 dBm Noise level=0 dBm Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0 Tx excessive retries:0 Invalid misc:0 Missed beacon:0

eth0 no wireless extensions.

root@rock64:~#

And, here is iw output:

root@rock64:/# iw dev wlx74da38f3cbcc info Interface wlx74da38f3cbcc ifindex 3 wdev 0x1 addr 74:da:38:f3:cb:cc type managed wiphy 0 txpower 12.00 dBm root@rock64:/#

[lwfinger]

Use 'iw list' to see the capabilities of the device. Does it show 2 bands present?

[Poincare1]

Yes, two bands are listed.

Requested output:

root@rock64:~# iw list
Wiphy phy0
max # scan SSIDs: 9
max scan IEs length: 2304 bytes
max # sched scan SSIDs: 0
max # match sets: 0
max # scan plans: 1
max scan plan interval: -1
max scan plan iterations: 0
Retry short limit: 7
Retry long limit: 4
Coverage class: 0 (up to 0m)
Supported Ciphers:
    * WEP40 (00-0f-ac:1)
    * WEP104 (00-0f-ac:5)
    * TKIP (00-0f-ac:2)
    * CCMP-128 (00-0f-ac:4)
Available Antennas: TX 0 RX 0
Supported interface modes:
     * IBSS
     * managed
     * AP
     * monitor
     * P2P-client
     * P2P-GO
Band 1:
    Capabilities: 0x1862
        HT20/HT40
        Static SM Power Save
        RX HT20 SGI
        RX HT40 SGI
        No RX STBC
        Max AMSDU length: 7935 bytes
        DSSS/CCK HT40
    Maximum RX AMPDU length 65535 bytes (exponent: 0x003)
    Minimum RX AMPDU time spacing: 16 usec (0x07)
    HT Max RX data rate: 150 Mbps
    HT TX/RX MCS rate indexes supported: 0-7, 32
    Bitrates (non-HT):
        * 1.0 Mbps
        * 2.0 Mbps
        * 5.5 Mbps
        * 11.0 Mbps
        * 6.0 Mbps
        * 9.0 Mbps
        * 12.0 Mbps
        * 18.0 Mbps
        * 24.0 Mbps
        * 36.0 Mbps
        * 48.0 Mbps
        * 54.0 Mbps
    Frequencies:
        * 2412 MHz [1] (30.0 dBm)
        * 2417 MHz [2] (30.0 dBm)
        * 2422 MHz [3] (30.0 dBm)
        * 2427 MHz [4] (30.0 dBm)
        * 2432 MHz [5] (30.0 dBm)
        * 2437 MHz [6] (30.0 dBm)
        * 2442 MHz [7] (30.0 dBm)
        * 2447 MHz [8] (30.0 dBm)
        * 2452 MHz [9] (30.0 dBm)
        * 2457 MHz [10] (30.0 dBm)
        * 2462 MHz [11] (30.0 dBm)
        * 2467 MHz [12] (30.0 dBm)
        * 2472 MHz [13] (30.0 dBm)
        * 2484 MHz [14] (disabled)
Band 2:
    Capabilities: 0x1862
        HT20/HT40
        Static SM Power Save
        RX HT20 SGI
        RX HT40 SGI
        No RX STBC
        Max AMSDU length: 7935 bytes
        DSSS/CCK HT40
    Maximum RX AMPDU length 65535 bytes (exponent: 0x003)
    Minimum RX AMPDU time spacing: 16 usec (0x07)
    HT Max RX data rate: 150 Mbps
    HT TX/RX MCS rate indexes supported: 0-7, 32
    Bitrates (non-HT):
        * 6.0 Mbps
        * 9.0 Mbps
        * 12.0 Mbps
        * 18.0 Mbps
        * 24.0 Mbps
        * 36.0 Mbps
        * 48.0 Mbps
        * 54.0 Mbps
    Frequencies:
        * 5170 MHz [34] (30.0 dBm)
        * 5180 MHz [36] (30.0 dBm)
        * 5190 MHz [38] (30.0 dBm)
        * 5200 MHz [40] (30.0 dBm)
        * 5210 MHz [42] (30.0 dBm)
        * 5220 MHz [44] (30.0 dBm)
        * 5230 MHz [46] (30.0 dBm)
        * 5240 MHz [48] (30.0 dBm)
        * 5260 MHz [52] (30.0 dBm)
        * 5280 MHz [56] (30.0 dBm)
        * 5300 MHz [60] (30.0 dBm)
        * 5320 MHz [64] (30.0 dBm)
        * 5500 MHz [100] (30.0 dBm)
        * 5520 MHz [104] (30.0 dBm)
        * 5540 MHz [108] (30.0 dBm)
        * 5560 MHz [112] (30.0 dBm)
        * 5580 MHz [116] (30.0 dBm)
        * 5600 MHz [120] (30.0 dBm)
        * 5620 MHz [124] (30.0 dBm)
        * 5640 MHz [128] (30.0 dBm)
        * 5660 MHz [132] (30.0 dBm)
        * 5680 MHz [136] (30.0 dBm)
        * 5700 MHz [140] (30.0 dBm)
        * 5745 MHz [149] (30.0 dBm)
        * 5765 MHz [153] (30.0 dBm)
        * 5785 MHz [157] (30.0 dBm)
        * 5805 MHz [161] (30.0 dBm)
        * 5825 MHz [165] (30.0 dBm)
        * 5920 MHz [184] (disabled)
        * 5940 MHz [188] (disabled)
        * 5960 MHz [192] (disabled)
        * 5980 MHz [196] (disabled)
        * 6000 MHz [200] (disabled)
        * 6020 MHz [204] (disabled)
        * 6040 MHz [208] (disabled)
        * 6060 MHz [212] (disabled)
        * 6080 MHz [216] (disabled)
Supported commands:
     * new_interface
     * set_interface
     * new_key
     * start_ap
     * new_station
     * set_bss
     * join_ibss
     * set_pmksa
     * del_pmksa
     * flush_pmksa
     * remain_on_channel
     * frame
     * set_channel
     * connect
     * disconnect
Supported TX frame types:
     * IBSS: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70 0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
     * managed: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70 0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
     * AP: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70 0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
     * AP/VLAN: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70 0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
     * P2P-client: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70 0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
     * P2P-GO: 0x00 0x10 0x20 0x30 0x40 0x50 0x60 0x70 0x80 0x90 0xa0 0xb0 0xc0 0xd0 0xe0 0xf0
Supported RX frame types:
     * IBSS: 0xd0
     * managed: 0x40 0xd0
     * AP: 0x00 0x20 0x40 0xa0 0xb0 0xc0 0xd0
     * AP/VLAN: 0x00 0x20 0x40 0xa0 0xb0 0xc0 0xd0
     * P2P-client: 0x40 0xd0
     * P2P-GO: 0x00 0x20 0x40 0xa0 0xb0 0xc0 0xd0
WoWLAN support:
     * wake up on anything (device continues operating normally)
software interface modes (can always be added):
     * monitor
interface combinations are not supported
Device supports scan flush.
 root@rock64:~# 

[lwfinger]

That output shows that the device and mac80211 have enabled the low and middle bands of 5G. The high band channels (above 180) are disabled. On my system, those channels do not even show in the list.

Any idea what channels 5G Aps in your neighborhood are using? Also be aware that 5G penetrates a lot less than 2.4G. On one of my APs, the signals are -18 and -37 dBm for 3.4 and 5G bands.

Have you run sudo iw dev wlx74da38f3cbcc scan | egrep "signal|SSID"'? That is an awful name for the device. Mine is "wls1".

[Poincare1]

Not sure why channels above 180 are disabled. I'm not doing anything special to either enable or disable bands or change the name. I just straight followed the procedure for DKMS install. Would love a name better than wlx74...

5ghz channel APs in the vicinity are on channels: 36, 40, 44, 48, 136, 149, 153, and 157. My 5G wifi AP is on channel 157.

In output of " iw dev wlx74da38f3cbcc scan | egrep "signal|SSID" " my 5G access point is not listed.

[lwfinger]

Any limitations would be in the user-space networking code, not in the driver.

You might be able to control the interface name in /etc/udev/rules.d/70-persistent-net.rules.

What country is your place of residence? Is CRDA installed on your computer?

[Poincare1]

I am in the USA. CRDA was not installed but it is now. Rebooted. Still not able to see any 5G WIFI APs.

[lwfinger]

What distro are you using, and what method of controlling networks? I will try to duplicate your results.

[Poincare1]

Using Debian Stretch with OpenMediaVault 4 for the Rock64.

[lwfinger]

The ARM processor should not make any difference. Unfortunately, I do not have any ARM systems for testing. The closest is a Keezel VPN appliance, which has an embedded RTL8192DU. The %G band works fine there.

[lwfinger]

I'm sorry I misled you. The RTL8723BU is 2.4G only. I had grabbed my RTL8811AU stick when I thought I had the RTL8723BU. The packages are nearly identical.

[Poincare1]

Hmmm. Well, I guess THAT solves the 5G problem. 📶