3

Preface : I had "No wifi adapter found" issue on my pc. I asked No wifi adapter found on Ubuntu 20.04.3 LTS, & the answer chili555 given was working fine.

Today after a restart, I am encountering a new issue. Now, wifi is enabled but it can't find any wifi networks. (though USB-Tethering works). The kernel version is 5.13.0-27-generic

  1. Output of iwconfig :
lo        no wireless extensions.
usb0      no wireless extensions.
wlp1s0    IEEE 802.11  ESSID:off/any  
          Mode:Managed  Access Point: Not-Associated   Tx-Power=3 dBm   
          Retry short limit:7   RTS thr:off   Fragment thr:off
          Power Management:on
docker0   no wireless extensions.
  1. sudo lshw -C network :
  *-network                 
       description: Wireless interface
       product: MEDIATEK Corp.
       vendor: MEDIATEK Corp.
       physical id: 0
       bus info: pci@0000:01:00.0
       logical name: wlp1s0
       version: 00
       serial: c8:94:02:c1:7a:7b
       width: 64 bits
       clock: 33MHz
       capabilities: pciexpress msi pm bus_master cap_list ethernet physical wireless
       configuration: broadcast=yes driver=mt7921e driverversion=5.13.0-27-generic firmware=____010000-20211014150922 latency=0 link=no multicast=yes wireless=IEEE 802.11
       resources: irq:88 memory:e0300000-e03fffff memory:e0400000-e0403fff memory:e0404000-e0404fff
  *-network
       description: Ethernet interface
       physical id: 1
       bus info: usb@1:2
       logical name: usb0
       serial: 82:75:76:11:9e:70
       capabilities: ethernet physical
       configuration: autonegotiation=off broadcast=yes driver=rndis_host driverversion=5.13.0-27-generic duplex=half firmware=RNDIS device ip=192.168.42.130 link=yes multicast=yes port=twisted pair
  1. rfkill list all :
0: hci0: Bluetooth
    Soft blocked: yes
    Hard blocked: no
1: phy0: Wireless LAN
    Soft blocked: no
    Hard blocked: no
  1. sudo iwlist scan:
lo        Interface doesn't support scanning.
usb0      Interface doesn't support scanning.
wlp1s0    No scan results
docker0   Interface doesn't support scanning.
  1. lspci -nnk | grep 0280 -A3:
01:00.0 Network controller [0280]: MEDIATEK Corp. Device [14c3:0608]
    Subsystem: MEDIATEK Corp. Device [14c3:0608]
    Kernel driver in use: mt7921e
    Kernel modules: mt7921e
  1. sudo dmesg | grep mt7:
[    3.629484] mt7921e 0000:01:00.0: enabling device (0000 -> 0002)
[    3.629700] mt7921e 0000:01:00.0: disabling ASPM  L1
[    3.629746] mt7921e 0000:01:00.0: ASIC revision: 79610010
[    3.712374] mt7921e 0000:01:00.0: HW/SW Version: 0x8a108a10, Build Time: 20211014150838a
[    3.724385] mt7921e 0000:01:00.0: WM Firmware Version: ____010000, Build Time: 20211014150922
[    3.754924] mt7921e 0000:01:00.0: Firmware init done
[    5.326846] mt7921e 0000:01:00.0 wlp1s0: renamed from wlan0

I have also tried sudo apt-get install --reinstall network-manager, sudo systemctl restart network-manager.service, sudo /etc/init.d/network-manager force-reload, Reboot mutiple times. But No luck !!

Arnob Saha
  • 63
  • 1
  • 2
  • 9
  • Please post the output of `lspci -nnk | grep 0280 -A3` and `uname -r`. Welcome to Ask Ubuntu! – Error404 Jan 30 '22 at 11:39
  • Hi @Someone, I have added those output on my post. – Arnob Saha Jan 30 '22 at 11:42
  • Hmmm, interesting. Seems like your device is new, is it? We've many questions regarding MediaTek 7000+ won't work on 20.04. So, I'd recommend upgrading to Ubuntu 21.10 with kernel 5.16. That's probably the best option there. – Error404 Jan 30 '22 at 11:51
  • Yes, my device is relatively new. Thanks for the recommendation. But, Isn't there any way to solve this issue for now ? – Arnob Saha Jan 30 '22 at 11:55
  • 1
    Actually, the device only works on kernel 5.15 or above (disclaimer: I have the same card as you). But you won't be able to install 5.15 on 20.04. – Error404 Jan 30 '22 at 11:59
  • Please verify that *both* of the udev files are present as described in the link you gave to my answer and that htere are no typos. Also, are there any clues in the log? `sudo dmesg | grep mt7` – chili555 Jan 30 '22 at 14:39
  • In terminal try `sudo iwconfig wlp1s0 power off && sudo iwconfig wlp1s0 txpower 18` or try my answer at https://askubuntu.com/a/1377785/300665 – Jeremy31 Jan 30 '22 at 14:40
  • Hi @chili555. I had already checked those files twice before posting this new question here. The output has been added to the post. – Arnob Saha Jan 30 '22 at 15:06
  • @Jeremy31 I have tried the `iwconfig` command you have given, But nothing changes. When I ran `sudo apt install build-essential flex bison` of your link, My terminal outputs `Waiting for cache lock: Could not get lock /var/lib/dpkg/lock-frontend. It is held by process 120`. May be this is because , `do-release-upgrade` command is running as `Someone` said in his answer. – Arnob Saha Jan 30 '22 at 15:16
  • Might need a reboot to be able to get the lock – Jeremy31 Jan 30 '22 at 15:51
  • Hey @Jeremy31 , After following your instructions, now everything gets messed up. Even my USB tethering is not working now. please help – Arnob Saha Jan 30 '22 at 17:51
  • In terminal `cd backports-5.15-rc6-1 && sudo make uninstall` Then reboot – Jeremy31 Jan 30 '22 at 17:54
  • Let us [continue this discussion in chat](https://chat.stackexchange.com/rooms/133648/discussion-between-arnob-saha-and-jeremy31). – Arnob Saha Jan 30 '22 at 17:57
  • Look here: https://askubuntu.com/questions/1380400/no-wifi-adapter-found-on-ubuntu-20-04-3-lts Maybe that will help. –  Jan 30 '22 at 18:32
  • @OliverLau Are you giving my question link to me ? what !! – Arnob Saha Jan 30 '22 at 18:34
  • Take a look here: [No-wifi-fix](https://askubuntu.com/questions/1380400/no-wifi-adapter-found-on-ubuntu-20-04-3-lts) Try this! –  Jan 30 '22 at 18:38

3 Answers3

1

You are using a relatively new and modern Wi-Fi adapter. As far as I know, this adapter doesn't work with the kernel version lower than 5.14. However, kernel 5.15.7+ is not installable on Ubuntu 20.04 LTS. If we look at kernel 5.14, it's EOL. So unfortunately, you cant use your Wi-Fi adapter with 20.04! You've to perform a fresh install of 21.10 (or upgrade using sudo do-release-upgrade) and follow the steps in my this answer and install kernel 5.16.

I'm using the same Wi-Fi adapter as you.

Error404
  • 6,920
  • 1
  • 26
  • 50
  • What do you mean by "kernel 5.15.7+ is not installable on Ubuntu 20.04 LTS"? – Pilot6 Jan 30 '22 at 13:27
  • It's because of the libc6 dependency. @Pilot6 see the link mentioned in my answer – Error404 Jan 30 '22 at 13:28
  • Hello @Someone, I have tried the steps from your given link.. But my kernel version didn't upgrade. Output of the commands :: https://go.dev/play/p/uY_3XaucA-v . When restarting, It enforces me to choose a kernel version between i) 5.16 ii) 5.16 (recovery mode) iii) 5.13 iv) 5.13(recovery mode). Choosing first 2 option does nothing. So I had to choose 5.13 kernel version. Can you please help me in this issue ? – Arnob Saha Feb 08 '22 at 16:46
1

In terminal do 

sudo ifconfig wlp1s0 up
sudo iwconfig wlp1s0 power off
sudo iwconfig wlp1s0 txpower 18

That is what we did in chat to get it running, https://chat.stackexchange.com/rooms/133648/discussion-between-arnob-saha-and-jeremy31

Jeremy31
  • 12,262
  • 9
  • 57
  • 113
-2

Run the module version sanity check, it will show whether the original module exists within the kernel.

sudo apt install --reinstall bcmwl-kernel-source

Ater checking for original module and if not found it will add the generic one.

Fahim Foysal
  • 1
  • 1