[Solved] Non functional ethernet connection, but wifi works

Issues & Assistance
1

Hey, I’m using a fresh install of CachyOS on a new PC and having issues getting it to detect an ethernet connection.

So far, I am assuming this must be a driver related issue with my motherboard
https://www.msi.com/Motherboard/MAG-Z890-TOMAHAWK-WIFI

lspci lists the following devices:

82:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. Device 5000 (rev 04)
83:00.0 Network controller: Intel Corporation Wi-Fi 7(802.11be) AX1775*/AX1790*/BE20*/BE401/BE1750* 2x2 (rev 1a)

I can confirm that the Ethernet port and related hardware does function - it works under windows with the relevant drivers from the mobo manufacturer installed. However, it doesn’t recognize anything on CachyOS (or the arch install medium) and despite searching I can’t find a driver package or trick for configuring it that does anything.

Does anyone know either the package I need or a procedure to set this hardware up to work via ethernet? I’ve been looking but I’ve had no luck so far. Would greatly appreciate any help with this.

2

Hey :wave:

Realtek is IMHO overall a pretty infamous manufacturer, let’s see if we can get there.

Can you narrow down the exact device type?

What does sudo dmesg | grep '82:00' show?

Is the interface there but just not up? Try ip link.

Run lcpci -v, it shows more details and the loaded and available kernel modules.

1 Like
3

Here are the results of those commands:
❯ sudo dmesg | grep ‘82:00’
[ 0.331966] pci 0000:82:00.0: [10ec:5000] type 00 class 0x020000 PCIe Endpoint
[ 0.331986] pci 0000:82:00.0: BAR 0 [io 0x3000-0x30ff]
[ 0.332011] pci 0000:82:00.0: BAR 2 [mem 0xb8200000-0xb820ffff 64bit]
[ 0.332027] pci 0000:82:00.0: BAR 4 [mem 0xb8210000-0xb8213fff 64bit]
[ 0.332175] pci 0000:82:00.0: supports D1 D2
[ 0.332175] pci 0000:82:00.0: PME# supported from D0 D1 D2 D3hot D3cold
[ 0.368454] pci 0000:82:00.0: Adding to iommu group 25

❯ ip link
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: wlan0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP mode DORMANT group default qlen 1000
link/ether e8:bf:b8:e5:21:58 brd ff:ff:ff:ff:ff:ff

lspci -v (trimmed to just the ethernet and wifi devices)

82:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. Device 5000 (rev 04)
Subsystem: Micro-Star International Co., Ltd. [MSI] Device 7e32
Flags: fast devsel, IRQ 255, IOMMU group 25
I/O ports at 3000 [disabled] [size=256]
Memory at b8200000 (64-bit, non-prefetchable) [disabled] [size=64K]
Memory at b8210000 (64-bit, non-prefetchable) [disabled] [size=16K]
Capabilities:

83:00.0 Network controller: Intel Corporation Wi-Fi 7(802.11be) AX1775*/AX1790*/BE20*/BE401/BE1750* 2x2 (rev 1a)
Subsystem: Rivet Networks Device 1774
Flags: bus master, fast devsel, latency 0, IRQ 19, IOMMU group 26
Memory at b8100000 (64-bit, non-prefetchable) [size=16K]
Capabilities:
Kernel driver in use: iwlwifi
Kernel modules: iwlwifi

Additionally, windows recognizes it as a “Killer E5000B” when it has drivers up.

4

Thanks. Looks okay so far, no errors, but indeed it has no kernel driver loaded or available; compare with the WiFi, which has iwlwifi loaded.

5

I found this:

I updated to the 6.11 kernel and my Intel® Killer™ E5000B 5G LAN r8126 isn’t detected. I also installed the dkms package and no go as well. pve 8.2.7. I’m on a very new z890 chipset mother board with Intel Ultra 265k

I was able to get the NIC working, it’s techinicall the: (Intel® Killer™ E5000B 5G LAN r8126)

So the chipset seems to be from realtek (r8126) and it is used by different vendors, e.g. Intel in their products.

Does a modprobe r8126 work?

There seems to be an AUR package available for this chipset:

$ yay -Ss r8126
aur/r8126-dkms 10.014.01-1 (+3 1.71) 
    Kernel module for Realtek RTL8126

$ yay -Si r8126-dkms
Repository                    : aur
Name                          : r8126-dkms
Version                       : 10.014.01-1
Description                   : Kernel module for Realtek RTL8126
URL                           : https://www.realtek.com/Download/List?cate_id=584
Licenses                      : GPL2
Groups                        : None
Provides                      : None
Depends On                    : dkms
Optional Deps                 : linux-headers  linux-lts-headers
Make Deps                     : None
Check Deps                    : None
Conflicts With                : r8126
Replaces                      : None
AUR URL                       : https://aur.archlinux.org/packages/r8126-dkms
First Submitted               : Wed 25 Sep 2024 10:14:58 PM CEST
Keywords                      : None
Last Modified                 : Sun 10 Nov 2024 07:37:43 PM CET
Maintainer                    : didi2002
Popularity                    : 1.708070
Votes                         : 3
Out-of-date                   : No

That is, if I detected the chipset correctly for you…

1 Like
6

Okay, so initially modprobe didn’t work, and paru seemed unwilling to install the driver you specified, so I used yay and fortunately that did the trick. Seems to work now and persists through boot as well.

Appreciate your help a lot, thank you.

7

Great, I’m happy it works now

1 Like
8

Paru and yay do exactly the same thing.
What many people don’t know is that paru needs to be confirmed with q in order to install packages.

2 Likes
9

Makes sense, appreciate you telling me. Been wracked by small oversights like this as is customary when trying out new things.

1 Like