Ubuntu 22.04.2 LTS下Realtek RTL8821CU USB无线网卡无法工作的求助

大家好，我是Ubuntu新手，目前在用Ubuntu 22.04.2 LTS系统。我有一块Realtek Semiconductor Co., Ltd.的RTL8111/8168/8411 PCIe千兆以太网卡，还有一块RTL8821CU USB无线网卡（lsusb里显示设备ID为0bda:c811），但这块无线网卡开箱即用不了，我查了网上的方法尝试解决，但还是没成功，想请大家帮忙看看问题出在哪。

以下是我收集的系统和设备相关信息：

1. lsusb命令输出 #

执行lsusb后，无线网卡已被识别：

Bus 002 Device 008: ID 0e8d:2004 MediaTek Inc. moto g22
Bus 002 Device 005: ID 058f:6361 Alcor Micro Corp. Multimedia Card Reader
Bus 002 Device 004: ID 0bda:c811 Realtek Semiconductor Corp. 802.11ac NIC
Bus 002 Device 003: ID 24ae:2013 Shenzhen Rapoo Technology Co., Ltd. Rapoo 2.4G Wireless Device
Bus 002 Device 002: ID 8087:0020 Intel Corp. Integrated Rate Matching Hub
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 003: ID 275d:0ba6  USB OPTICAL MOUSE
Bus 001 Device 002: ID 8087:0020 Intel Corp. Integrated Rate Matching Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

2. sudo lshw -C network命令输出 #

*-network
description: Ethernet interface
product: RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller
vendor: Realtek Semiconductor Co., Ltd.
physical id: 0
bus info: pci@0000:02:00.0
logical name: enp2s0
version: 06
serial: 9e:07:07:e3:98:a0
capacity: 1Gbit/s
width: 64 bits
clock: 33MHz
capabilities: pm msi pciexpress msix vpd bus_master cap_list ethernet physical tp 10bt 10bt-fd 100bt 100bt-fd 1000bt-fd autonegotiation
configuration: autonegotiation=on broadcast=yes driver=r8168 driverversion=8.049.02-NAPI latency=0 link=no multicast=yes port=twisted pair
resources: irq:25 ioport:e800(size=256) memory:f9fff000-f9ffffff memory:f9ff8000-f9ffbfff

*-network
description: Ethernet interface
physical id: 5
bus info: usb@2:1.6
logical name: enx463925c9264f
serial: 46:39:25:c9:26:4f
capabilities: ethernet physical
configuration: autonegotiation=off broadcast=yes driver=rndis_host driverversion=5.19.0-38-generic duplex=half firmware=RNDIS device ip=192.168.34.226 link=yes multicast=yes port=twisted pair

3. 安装r8168驱动后的dkms status输出 #

我已经安装了r8168驱动，执行sudo dkms status得到：

broadcom-sta/6.30.223.271, 5.19.0-38-generic, x86_64: installed
r8168/8.049.02, 5.19.0-38-generic, x86_64: installed
rtl8821CU/5.4.1: added

4. 重启时的错误日志 #

重启系统时，我看到以下错误信息：

[ 1.333512] r8168 0000:02:00.0 (unnamed net_device)(uninitialized): invalid ether addr 00:00:00:00:00:00

后续尝试的解决步骤及结果 #

感谢@chili555的回复，我按照建议尝试了操作，但问题还是没解决，以下是具体过程：

尝试移除旧驱动 #

执行sudo dkms remove rtl8821CU/5.4.1 --all时，出现错误：

Error! The module/version combo: rtl8821CU-5.4.1 is not located in the DKMS tree.

安装新的RTL8821CU驱动 #

进入~/8821cu-20210916目录，执行sudo ./install-driver.sh，安装过程输出如下：

: ---------------------------
: install-driver.sh v20230227
: x86_64 (architecture)
: 4/4 (in-use/total processing units)
: 12246640 (total system memory)
: 5.19.0-38-generic (kernel version)
: gcc (Ubuntu 11.3.0-1ubuntu1~22.04) 11.3.0
: dkms-2.8.7
EFI variables are not supported on this system
: ---------------------------
Checking for previously installed drivers.
: ---------------------------
Starting installation.
Installing 8821cu.conf to /etc/modprobe.d
The dkms installation routines are in use.
Copying source files to /usr/src/rtl8821cu-5.12.0.4
Creating symlink /var/lib/dkms/rtl8821cu/5.12.0.4/source -> /usr/src/rtl8821cu-5.12.0.4
The driver was added to dkms successfully.
: ---------------------------
Kernel preparation unnecessary for this kernel. Skipping...
Building module:
cleaning build area...
./dkms-make.sh.................................
Signing module:
- /var/lib/dkms/rtl8821cu/5.12.0.4/5.19.0-38-generic/x86_64/module/8821cu.ko
EFI variables are not supported on this system
/sys/firmware/efi/efivars not found, aborting.
cleaning build area...
Compile time: 313.36 seconds
The driver was built by dkms successfully.
: ---------------------------
8821cu.ko:
Running module version sanity check.
- Original module
- No original module exists within this kernel
- Installation
- Installing to /lib/modules/5.19.0-38-generic/updates/dkms/
depmod............
The driver was installed by dkms successfully.
: ---------------------------
Info: Upgrade this driver with the following commands as needed:
$ git pull
$ sudo sh install-driver.sh
Note: Upgrades to this driver should be performed before distro upgrades.
Note: Upgrades can be performed as often as you like.
Note: Work on this driver is continuous.
: ---------------------------
Do you want to edit the driver options file now? (recommended) [Y/n]
Do you want to apply the new options by rebooting now? (recommended) [Y/n]

安装过程中多次提示EFI variables are not supported on this system，我不确定这个提示是否重要，当时选择了Y确认编辑配置并重启系统，但问题依旧。

安装后的dkms status输出 #

再次执行sudo dkms status，显示新驱动已安装：

broadcom-sta/6.30.223.271, 5.19.0-38-generic, x86_64: installed
rtl8821cu/5.12.0.4, 5.19.0-38-generic, x86_64: installed

dmesg相关日志 #

执行sudo dmesg | grep 8821得到：

[sudo] password for rgtm:
[   21.202833] RTW: rtl8821cu v5.12.0.4-1-g9241a6516.20210916_COEX20200730-5151
[   21.202835] RTW: rtl8821cu BT-Coex version = COEX20200730-5151
[   21.624773] usbcore: registered new interface driver rtl8821cu
[   21.655048] rtl8821cu 2-1.3:1.0 wlx1cbfce9da648: renamed from wlan0

目前无线网卡还是无法正常工作，希望有遇到过类似问题的朋友能给我一些建议，谢谢大家！

备注：内容来源于stack exchange，提问作者Rgtm