I am just looking for a working image that would have the 8821CU working. I've been able to make it work on Ordoid HC-4, but on N2+, it didn't work.

Also, my N2 setup on armbian had some problem. I launched sudo armbian-config, tried to install headers and firmware, but I couldn't. It didn't provide any error message, it just showed the loading bar and quitted quickly (as if it completed). Then I tried Nigthly and I was able to download headers and firmware, but still wasn't able to get 8821CU working (now thinking about it, I don't recall checking out if it was detected from lsusb... I'm not entirely sure). Then I went back to stable and now I'm no longer able to boot. Should I fresh install focal again or try another image? DId I miss something during installation to get 8821CU working?

Thank you.

Moved to P2P help.

I've moved to DietPi, it works fine now. I believe that the problem could have been solved by entering the usb_modeswtich command twice (see git page of bektrou  8821CU ). That being said, I don't know what was the issue with armbian-config software installation.

 

@jogoodDid you compile the driver from https://github.com/brektrou/rtl8821CU?

I recognised that the Armbian kernel ships with an rtl8811cu/8821cu.ko module. I tried to get an RTL8811CU WiFi adapter working with it on NanoPi R4S 5.15.25-rockchip64. It gets detected, the driver is loaded, the network interface is there, one can scan for SSIDs, but wpa_supplicant fails to authentication with a connection error. It works however well when compiling from above sources via DKMS. I'm wondering what the difference between this and the Armbian kernel driver is. I guess it is not in upstream, so I wonder whether Armbian uses https://github.com/fastoe/RTL8811CU, a fork which isn't up-to-date anymore and did no actual changes (apart of readme) to the sources. But as of the different project name, one may find it when searching for RTL8811CU drivers explicitly.

 

Reported driver versions match 100%: v5.4.1_28754.20180921_COEX20180712-3232

But modinfo reports a different "srcversion": "94DBED2BC6C5DBB4E7F9335" (Armbian) vs "960CCC648A0E0369171A2C9" (GitHub repo).

 

@Wernerdo you know whether all/this driver is coming from Linux upstream sources or added from other sources for Armbian kernel builds? Ah, I should probably check back with Edge kernel, whether it has the same issue.

6 minutes ago, MichaIng said:

do you know whether all/this driver is coming from Linux upstream sources or added from other sources for Armbian kernel builds?

Not from scratch. Take a look here: https://github.com/armbian/build/blob/master/lib/compilation-prepare.sh

All 3rd party drivers are included there.

Ah thanks, found it, uses the same https://github.com/brektrou/rtl8821CU repo, but a specific commit. That was raised after last release via https://github.com/armbian/build/commit/98ccbc9d264e6aee3ac69692bb4ef694c079eb17, pointing to https://github.com/brektrou/rtl8821CU/commit/de68bd50671ad8a5c09af97def3f2059b4a088aa now. Trying edge kernel...

 

Okay works very well with edge kernel indeed. So again, I can only speak for RTL8811CU (not RTL8821CU) on NanoPi R4S (Rockchip RK3399): It compiles well on "current" kernel (Linux 5.15, Armbian 22.02.1) and works well OOTB on "edge" kernel (Linux 5.16, Armbian 22.05.0 at time of writing) where the source commit has been raised to nearly latest.

 

Now I realised that OP was able to get it working on Odroid HC4 but not on N2+. So I'll try it on N2+ as well the next days and report back.