Hello everybody,
I recently had updated the whole system and it doesn't allow me to connect to my wifi network, neither it sees any wifi connection.

I don't know much about informatics in general, but maybe this can be useful:

inxi -N

Network:
Device-1: Realtek RTL8821CE 802.11ac PCIe Wireless Network Adapter
driver: N/A
Device-2: Realtek RTL8111/8168/8411 PCI Express Gigabit Ethernet
driver: r8169

Maybe the journal will show an error regarding this card:

sudo journalctl -b | grep 8821

also show any messages NetworkManger might have:

sudo systemctl status NetWorkmanager

Did this start after updating the kernel to linux 5.1.5? See your pacman log for what was most recently updated in /var/log/pacman.log

sudo journalctl -b | grep 8821

lug 04 12:01:22 BooMiki kernel: Bluetooth: hci0: RTL: rtl: examining hci_ver=08 hci_rev=000c lmp_ver=08 lmp_subver=8821
lug 04 12:01:22 BooMiki kernel: Bluetooth: hci0: RTL: rtl: loading rtl_bt/rtl8821c_fw.bin
lug 04 12:01:22 BooMiki kernel: Bluetooth: hci0: RTL: rtl: loading rtl_bt/rtl8821c_config.bin
lug 04 12:38:18 BooMiki sudo[7790]: siciliano : TTY=pts/0 ; PWD=/home/siciliano ; USER=root ; COMMAND=/usr/bin/modprobe rtl8821CE

sudo systemctl status NetWorkmanager

Unit NetWorkmanager.service could not be found.

And yes, I updated Linux from 5.0.9-1 to 5.1.15-1

Sorry, needs to be sudo systemctl status NetWorkManager
And this is a bluetooth device?

I just tried sudo systemctl status NetWorkManager

Unit NetWorkManager.service could not be found

And it's not a bluetooth device

I tried sudo systemctl status NetworkManager

NetworkManager.service - Network Manager
   Loaded: loaded (/usr/lib/systemd/system/NetworkManager.service; enabled; vendor>
  Drop-In: /usr/lib/systemd/system/NetworkManager.service.d
           └─NetworkManager-ovs.conf
   Active: active (running) since Thu 2019-07-04 12:09:30 CEST; 2h 10min ago
     Docs: man:NetworkManager(8)
 Main PID: 2677 (NetworkManager)
    Tasks: 3 (limit: 4915)
   Memory: 8.9M
   CGroup: /system.slice/NetworkManager.service
           └─2677 /usr/sbin/NetworkManager --no-daemon

lug 04 12:09:36 BooMiki NetworkManager[2677]: <info>  [1562234976.0640] audit: op=>
lug 04 12:09:45 BooMiki NetworkManager[2677]: <info>  [1562234985.4072] audit: op=>
lug 04 12:24:43 BooMiki NetworkManager[2677]: <info>  [1562235883.8442] audit: op=>
lug 04 12:24:47 BooMiki NetworkManager[2677]: <info>  [1562235887.2475] audit: op=>
lug 04 12:35:22 BooMiki NetworkManager[2677]: <info>  [1562236522.0888] audit: op=>

Any output for lsmod | grep 8821?
Still trying to get some error info, see if sudo journalctl | grep Network shows any errors.

Ok, the first one doesn't give anything

for sudo journalctl | grep Network

ug 04 12:02:49 BooMiki kdeconnectd[746]: kdeconnect.core: Sending onNetworkChange to  1  LinkProviders
lug 04 12:09:20 BooMiki polkit-kde-authentication-agent-1[735]: Message of action:  "Autenticazione richiesta per riavviare 'NetworkManager.service'."
lug 04 12:09:30 BooMiki kdeconnectd[746]: propsReply "Interfaccia «org.freedesktop.DBus.Properties» inesistente sull'oggetto nel percorso /org/freedesktop/NetworkManager"
lug 04 12:09:30 BooMiki kdeinit5[691]: propsReply "Interfaccia «org.freedesktop.DBus.Properties» inesistente sull'oggetto nel percorso /org/freedesktop/NetworkManager"
lug 04 12:09:30 BooMiki kdeconnectd[746]: nmReply "Interfaccia «org.freedesktop.NetworkManager» inesistente sull'oggetto nel percorso /org/freedesktop/NetworkManager"
lug 04 12:09:30 BooMiki kdeinit5[691]: nmReply "Interfaccia «org.freedesktop.NetworkManager» inesistente sull'oggetto nel percorso /org/freedesktop/NetworkManager"
lug 04 14:20:13 BooMiki sudo[11268]: siciliano : TTY=pts/0 ; PWD=/home/siciliano ; USER=root ; COMMAND=/usr/bin/systemctl status NetworkManager
lug 04 14:51:27 BooMiki NetworkManager[2677]: <info>  [1562244687.9677] audit: op="statistics" arg="refresh-rate-ms" pid=730 uid=1000 result="success"
lug 04 14:51:30 BooMiki NetworkManager[2677]: <info>  [1562244690.9964] audit: op="statistics" arg="refresh-rate-ms" pid=730 uid=1000 result="success"

esistente sull'oggetto nel percorso
Means "inexistent on the object of the path"

Still nothing wrong in the logs, are you trying to connect with Wifi during this session/boot or have you switched to ethernet?

I switched to Ethernet.

It worked until last night when I updated it, I turned off the notebook and when I turned it on today, it was this way.

Logs won't show anything wrong, if you use ethernet, the -b switch in the journalctl call means only output since last reboot 🙂
Though what I find everywhere is that the card you list in the first post is not supported in linux, so I do not understand how it ever worked.
To test changes in the kernel only, you can revert back to linux 5.0.9 if that is still in your cache and you have no modules depending on linux, check with pacman -Qi linux, look for the required by line. If you don't use nvidia or virtualbox, you can sudo pacman -U /var/cache/pacman/pkg/linux-5.0.9-1-x86_64.pkg.tar.xz

Oh God, do I have to test it without using ethernet?

For logs, yes you will have to use the Wifi device. To downgrade, no.

sudo systemctl status NetworkManager
● NetworkManager.service - Network Manager
Loaded: loaded (/usr/lib/systemd/system/NetworkManager.service; enabled; vendor>
Drop-In: /usr/lib/systemd/system/NetworkManager.service.d
└─NetworkManager-ovs.conf
Active: active (running) since Thu 2019-07-04 18:01:39 CEST; 7min ago
Docs: man:NetworkManager(8)
Main PID: 422 (NetworkManager)
Tasks: 3 (limit: 4915)
Memory: 14.8M
CGroup: /system.slice/NetworkManager.service
└─422 /usr/sbin/NetworkManager --no-daemon

lug 04 18:01:42 BooMiki NetworkManager[422]: <info> [1562256102.5997] keyfile: ad>
lug 04 18:01:42 BooMiki NetworkManager[422]: <info> [1562256102.7292] settings: (>
lug 04 18:01:42 BooMiki NetworkManager[422]: <info> [1562256102.7300] device (eno>
lug 04 18:01:43 BooMiki NetworkManager[422]: <info> [1562256103.1046] ovsdb: Impo>
lug 04 18:01:43 BooMiki NetworkManager[422]: <info> [1562256103.1063] bluez: use >
lines 1-17

I can't either downgrade it, is there something else I can do?

  • demm replied to this.

    Please make sure to get logs with actual errors, all you show so far is all perfectly working, repeat logs as I asked before, when you disable ethernet, also make sure to read https://kaosx.us/docs to give helpful info.

    ArcesilaoII I can't either downgrade it

    What does that mean? Downgrading can always be done, just a matter of wanting to.

      sudo pacman -U /var/cache/pacman/pkg/linux-5.0.9-1-x86_64.pkg.tar.xz

      Password:
      caricamento dei pacchetti in corso...
      errore: '/var/cache/pacman/pkg/linux-5.0.9-1-x86_64.pkg.tar.xz': impossibile trovare o leggere il pacchetto

      → Impossible finding or reading the package