[SOLVED] USB Wifi Adapter worked during install, but not post-install

teagueathan · 2019-12-18 04:13:09

Hello there!
While I was installing Arch Linux, I was able to get a USB Wifi Adapter working by disabling rfkill and connecting to a network via wpa_cli, which allowed me connection to the internet.
However, after the installation, I am unable to use the same adapter as the driver isn't even registered by the system according to dmesg (it should be covered under rt2800usb).
I believe this might be due to required packages I forgot to include during the pacstrap command, however I am unsure.
My question is: why am I not able to use the same adapter post-install?

Last edited by teagueathan (2019-12-19 10:31:03)

seth · 2019-12-18 07:32:24

Because something went wrong… we'll need some actual information to make an informed comment.

Please provide the outputs of

ip a
lsusb
lspci
lsmod
sudo modprobe rt2800usb
uname -a
pacman -Qs linux
sudo journalctl -b

You can use https://wiki.archlinux.org/index.php/Pastebin to feed longer outputs directly into a pastebin service.

Welcome to the forum.

teagueathan · 2019-12-18 21:51:19

Outputs:

 ip a

Generally the USB would be listed as wlan0, but there's no such entry.

1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever

lsusb wasn't a valid command, but it probably should be.

 lspci

00:00.0 Host bridge: Intel Corporation Device 3e35 (rev 0b)
00:02.0 VGA compatible controller: Intel Corporation Device 3ea1
00:04.0 Signal processing controller: Intel Corporation Xeon E3-1200 v5/E3-1500 v5/6th Gen Core Processor Thermal Subsystem (rev 0b)
00:08.0 System peripheral: Intel Corporation Xeon E3-1200 v5/v6 / E3-1500 v5 / 6th/7th/8th Gen Core Processor Gaussian Mixture Model
00:12.0 Signal processing controller: Intel Corporation Cannon Point-LP Thermal Controller (rev 30)
00:14.0 USB controller: Intel Corporation Cannon Point-LP USB 3.1 xHCI Controller (rev 30)
00:14.2 RAM memory: Intel Corporation Cannon Point-LP Shared SRAM (rev 30)
00:15.0 Serial bus controller [0c80]: Intel Corporation Cannon Point-LP Serial IO I2C Controller #0 (rev 30)
00:16.0 Communication controller: Intel Corporation Cannon Point-LP MEI Controller #1 (rev 30)
00:17.0 SATA controller: Intel Corporation Cannon Point-LP SATA Controller [AHCI Mode] (rev 30)
00:1d.0 PCI bridge: Intel Corporation Cannon Point-LP PCI Express Root Port #9 (rev f0)
00:1e.0 Communication controller: Intel Corporation Device 9da8 (rev 30)
00:1f.0 ISA bridge: Intel Corporation Device 9d85 (rev 30)
00:1f.3 Audio device: Intel Corporation Cannon Point-LP High Definition Audio Controller (rev 30)
00:1f.4 SMBus: Intel Corporation Cannon Point-LP SMBus Controller (rev 30)
00:1f.5 Serial bus controller [0c80]: Intel Corporation Cannon Point-LP SPI Controller (rev 30)
01:00.0 Network controller: Realtek Semiconductor Co., Ltd. RTL8821CE 802.11ac PCIe Wireless Network Adapter

Output of lsmod can be found here: http://codepad.org/0UrCszVF

 modprobe rt2800usb

This command had no output (I currently only have a root user on my Arch machine).

 uname -a

Linux ArchS145 5.4.3-arch1-1 #1 SMP PREEMPT Fri, 13 Dec 2019 09:39:02 +0000 x86_64 GNU/Linux

 pacman -Qs linux

local/archlinux-keyring 20191018-2
    Arch Linux PGP keyring
local/base 2-2
    Minimal package set to define a basic Arch Linux installation
local/filesystem 2019.10-2
    Base Arch Linux files
local/iptables 1:1.8.3-3
    Linux kernel packet control tool (using legacy interface)
local/keyutils 1.6.1-3
    Linux Key Management Utilities
local/kmod 26-3
    Linux kernel module management tools and library
local/libutil-linux 2.34-8
    util-linux runtime libraries
local/linux 5.4.3.arch1-1
    The Linux kernel and modules
local/linux-api-headers 5.3.1-2
    Kernel headers sanitized for use in userspace
local/linux-firmware 20191118.e8a0f4c-2
    Firmware files for Linux
local/linux-headers 5.4.3.arch1-1
    Headers and scripts for building modules for the Linux kernel
local/man-pages 5.04-2
    Linux man pages
local/pacman-mirrorlist 20191001-2
    Arch Linux mirror list for use by pacman
local/util-linux 2.34-8
    Miscellaneous system utilities for Linux

Output of journalctl -b can be found here: http://www.rafb.me/results/Plvmds72.html

seth · 2019-12-18 22:02:16

lsusb is part of the usbutils package.

Installed kernel matches the running one, rt2800usb wasn't loaded at the time you dumped lsmod but apparently loads w/o error (re-check lsmod) but your wifi chip seems

01:00.0 Network controller: Realtek Semiconductor Co., Ltd. RTL8821CE 802.11ac PCIe Wireless Network Adapter

which would be https://aur.archlinux.org/packages/rtl8821ce-dkms-git/ - unless you've an external usb wifi dongle?

teagueathan · 2019-12-18 22:39:28

Yes, due to the nature of how new this laptop is, I had to use a dongle for connection (before Arch, I was using Fedora 30).
I have tried installing that driver, but whenever I try to install it manually it fails. The funny thing is, this problem only happens when trying to install it manually, so if I install it via yay or something like that, it should work. Yet I have no internet connection. Perhaps I should try a fresh install, adding what I need while I've chroot'd into the system?

Last edited by teagueathan (2019-12-18 22:39:51)

seth · 2019-12-19 07:30:31

You don't have to re-install, you can just arch-chroot into the already installed system from the installation iso (skipping all other steps)
Please elaborate on "try to install it manually it fails" and definitively install usbutils to provide lsusb for the actual devices (ie. notably your wifi dongle)

teagueathan · 2019-12-19 10:32:36

I arch-chrooted and installed the stuff I needed to get wifi working, including a working driver for my original wifi chip, so I don't even need the dongle anymore.
Thanks!

Last edited by teagueathan (2019-12-19 10:32:55)

Arch Linux

#1 2019-12-18 04:13:09

[SOLVED] USB Wifi Adapter worked during install, but not post-install

#2 2019-12-18 07:32:24

Re: [SOLVED] USB Wifi Adapter worked during install, but not post-install

#3 2019-12-18 21:51:19

Re: [SOLVED] USB Wifi Adapter worked during install, but not post-install

#4 2019-12-18 22:02:16

Re: [SOLVED] USB Wifi Adapter worked during install, but not post-install

#5 2019-12-18 22:39:28

Re: [SOLVED] USB Wifi Adapter worked during install, but not post-install

#6 2019-12-19 07:30:31

Re: [SOLVED] USB Wifi Adapter worked during install, but not post-install

#7 2019-12-19 10:32:36

Re: [SOLVED] USB Wifi Adapter worked during install, but not post-install

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