RTL8125 2.5GbE Ethernet port not working in Ubuntu 24.04

Support and Help
1

Hi.

I am by no means good at troubleshooting Linux, but I have built dozens of computers over the years, and helped many people with their computer stuff, and I have never had even one problem with Ethernet connections to the Internet. Here is my current problem, no Ethernet connection to my LAN:

Ubuntu Version: Ubuntu 24.04.2 LTS

Desktop Environment (if applicable): ubuntu:GNOME

Problem Description:

Once I get the wireless-info script working, or I learn a workaround, I can start a new post in Networking and ask for help diagnosing my Ethernet connection (actually, connection failure).
I am doing all this work on the target system, using its WiFi connection, which always works, and this is what I see:

I’m following the instructions at

and I run the script wireless-info but it never says anything about pastebin, as follows:

james@NUC14Ess:~/Downloads$ ./wireless-info
[sudo] password for james: 

Results saved in "/home/james/Downloads/wireless-info.txt".

Results also archived in "/home/james/Downloads/wireless-info.tar.gz", as they exceed the 19.5 kB size limit for ".txt" attachments on the Ubuntu Forums.

james@NUC14Ess:~/Downloads$

Relevant System Information:
A new (1-week old) ASUS NUC 14 Essential Barebones with the “top-of-the-line” Intel Core 3 N355 CPU option (Model # NUC14MNK35*), and these two items added:

Kingston RAM: Fury Impact 16GB 4800MT/s DDR5 CL38 SODIMM XMP Ready Laptop Memory Single Module KF548S38IB-16
https://shop.kingston.com/products/impact-ddr5-laptop-memory?variant=41738521968832

Crucial P3 1TB PCIe Gen3 3D NAND NVMe M.2 SSD, up to 3500MB/s - CT1000P3SSD8

Screenshots or Error Messages:

lspci output includes this one item relevant to Ethernet:
01:00.0 Ethernet controller [0200]: Realtek Semiconductor Co., Ltd. RTL8125 2.5GbE Controller [10ec:8125] (rev 0c)
Subsystem: ASUSTeK Computer Inc. RTL8125 2.5GbE Controller [1043:88e8]
Kernel modules: r8169

The computer’s “BIOS” / UEFI setup screen shows the LAN controller Enabled.

What I’ve Tried:

I have tried both the CLI and GUI versions of NetworkManager and similar tools, and I messed around (Newbie) in them and somehow succeeded in adding an entry called “Ethernet connection 1” (it wasn’t there before I did that) and I entered the correct Ethernet MAC address from the setup screen, then I did

james@NUC14Ess:~$ sudo systemctl restart NetworkManager
and that ran with no complaining, and the network indicator at top right of my screen apparently really does restart, but still no joy.

and it doesn’t show up as the “Device” in this report:

james@NUC14Ess:~$ nmcli connection show
NAME                   UUID                                  TYPE      DEVICE 
Home-N                 c3289016-c905-488a-990f-b2ccacdb40be  wifi      wlo1   
lo                     198d2940-7150-4a14-9908-935c4fffa7bd  loopback  lo     
Ethernet connection 1  14dfe36f-93f6-4854-a1f5-fdf685c395af  ethernet  --     
james@NUC14Ess:~$

I disconnected the cable from the Gigabit Ethernet hub in the Study to a working_device (the VoIP adapter, which has been working for about 15 years) and plugged it in instead to the Ethernet jack on the NUC, where it has been through all this testing, and yes, I did re-seat it and I did hear it “click”.

In case it matters: There are lots of complaints on various forums of baffling Ethernet problems in Ubuntu 24.04.x.

I will greatly appreciate any ideas for further testing, troubleshooting, driver installations, etc…

Sincerely,

Jim Harris

1 Like
2

The wireless info script won’t show much for ethernet troubleshooting as it was designed for wifi. It should have asked if you want to upload results at some point, alternatively you could just cat wireless-info.txt | nc termbin.com 9999 and that would upload to termbin and give you a URL

2 Likes
3

Thanks, @Jeremy31.

I will reply on two different topics, as you have introduced a new one. This is my first reply: If

is not actually the network connection troubleshooting tool this forum wants newcomers (or anyone) tho use, I recommend it be brought to the attention of someone who can fix it. The explanation included in that page is that the tool is just retaining an old name, that it actually works well for Ethernet too. Can you pass on this info to someone who can fix that, or tell me how to do that?

4

Thanks again, @Jeremy31, and here is my second reply:

Here is what I see, which has no such info as you describe, i.e. a URL:

james@NUC14Ess:~/Downloads$ cat wireless-info.txt | nc termbin.com 9999
james@NUC14Ess:~/Downloads$

5

I see the issue, termbin.com is down for some reason now the alternative is to cat wireless-info.txt | pastebinit

Looks like posting the script results work if posted as a spoiler

6

james@NUC14Ess:~/Downloads$ cat wireless-info.txt | pastebinit
Failed to contact the server: The read operation timed out
james@NUC14Ess:~/Downloads$

7

I don’t understand “if posted as a spoiler”.

8

I am getting used to Discourse so see if https://meta.discourse.org/t/how-to-create-spoilers-in-discourse/190662 helps, there are some options in the reply window if you click the gear icon but that is just blur spoiler

9

@Jeremy31, I tried your alternate cat command and I think it worked; I got:

james@NUC14Ess:~/Downloads$ cat wireless-info.txt | pastebinit
https://dpaste.com/4NR5WCGA7
james@NUC14Ess:~/Downloads$

and I tried to follow the info about “spoiler” and I have absolutely no idea what that’s about.

Anyway, now that my wireless-info.txt is uploaded (right?) is there anything I should do but wait for someone (you?) to read it and reply to this thread?

Is there a better diagnostic tool that may look more closely at my Ethernet stuff than wireless-info does? If so, please point me down that path.

Thanks again.

Jim

10

You can try sudo apt install git
git clone https://github.com/notpeelz/r8125.git
cd r8125/src
make

Ignore some errors, then
zstd r8125.ko
sudo cp r8125.ko.zst /lib/modules/$(uname -r)/kernel/drivers/net/ethernet/realtek/
echo "blacklist r8169" | sudo tee /etc/modprobe.d/r8169.conf
sudo depmod -a
Reboot

On the other subject, I think I have the script fixed by using pastebinit once again

1 Like
11

Thanks again, Jeremy.

Of course, at this point I have no idea what I will be “trying” (remember, I’m really a Newbie compared to folks like you), but I will try to get to it after supper (about 4 hours from now).

I will be very limited on time for this project after that until Monday.

Meanwhile, I discovered this in wireless-info.txt after my my first run, then installed dkms and re-ran wireless-info and that “command not found” disappeared, and that is the wireless-info.txt that I uploaded. It seems there should be another instruction in the guideline to install dkms; right?

dkms

./wireless-info: line 206: dkms: command not found

BTW, have you noticed, as I have, that in recent days/weeks there are lots of forum posts about Ubuntu 24.04.x Ethernet problems? Before I do any of this further installing of tools and venturing further down this very unfamiliar path, I will try to update to 24.04.5 or .6 or whatever is latest; it seems they are releasing a point update every 2 or 3 days (literally).

Jim

12

The dkms not found is not an issue, it means you don’t have it installed. DKMS is used to build an out of tree kernel module automatically when a new kernel is installed rather than do it manually after a kernel update and reboot. I don’t think there is a 24.04.5 at this time and I think I saw something about kernel support for you ethernet in 6.12 or 6.13 kernel.

The errors I mentioned are because of the makefile instructions and I am not one to have someone use sudo for make as that shouldn’t be needed, sudo should only be needed for make install

1 Like
13

Thanks again, Jeremy.

Yes, I made the same mistake as whoever set up that link error I have reported about the Releases 24.04.1 link going to 22.04.1 files. Sorry for the confusion.

As of now, I think I am already on the latest release, which is apparently 24.04.2.

I will hopefully have time to try your suggestions after supper.

Jim

14

If that code works, I could see if I can make a dkms.conf so it is automatically updated and make some changes to that Makefile

15

OK, I will be sure to post my results in this thread.

16

@Jeremy31,

Here is my “report of results”:

WONDERFUL!

Not only works, but works at 1 Gbps.

Thank you; Thank you; Thank you!

You have made a great contribution!

To make it even greater, I strongly recommend you pass this on to:

  • Ubuntu Release staff (at Canonical?) to let them know they need to include that r8125 thingie or whatever it is we did to fix the problem, and they need to hurry, because there are a lot of people who will have the same mysterious failure of their Ethernet until it is fixed.
  • ASUS to let them know that they need to have their sellers add a slip of paper to every package shipping one of the whole family of NUCs that this missing feature affects (you have the details in my Original Post), and add it to their WWW site about them, and include it in their invoices/order info, etc… This is a HUGE problem that ASUS must not be aware of, because I called them a couple days ago and I got a Return Material Authorization, because they promise to support their product when it is running Ubuntu 24.04.x LTS, and they think they need to repair the NUC and ship it back to me, and there is nothing wrong with it!

Do you have the connections called for to pass this along to the above, and to others that would be affected?

Thanks again! Wow! Wow!

Jim

17

Ok, I found a way to use dkms, go into the r8125/src directory in the file manager and right click in an empty space and create a new file, name it dkms.conf and paste in

MAKE="'make' modules KVER=${kernelver}"
CLEAN="make clean"
BUILT_MODULE_NAME=r8125
DEST_MODULE_NAME="r8125"
DEST_MODULE_LOCATION="/updates"
PACKAGE_NAME=r8125
PACKAGE_VERSION=4.1
AUTOINSTALL=yes

Save the file, then open terminal
cd r8125/src
sudo dkms add .
sudo dkms install r8125/4.1
To anyone else that my find this also do echo "blacklist r8169" | sudo tee /etc/modprobe.d/r8169.conf

1 Like
18

Edited the title to show the problem (Ethernet port not working) that future users will care most about.

1 Like
19

I got telephone confirmation today (Feb. 25) from ASUS “Tech Support” / “Customer Service” that the problem and fix have been confirmed. Unfortunately, this information apparently has not yet had significant distribution in ASUS-related circles (distributors, dealers, their own WWW pages on the topic, etc.).

I find nothing from Ubuntu on this.

Does anyone (preferably a forum official/manager or whatever that role is called) know how and want to let Ubuntu/Canonical know about this?

20

Is someone on this forum (e.g. a “manager” or person with otherwise elevated moxie/respect) able and willing to notify Ubuntu/Canonical of this defect? The longer it remains un-patched, and even unknown to Tech Support staff worldwide in both hardware channels (distributors, sellers, etc.) and Ubuntu channels, the more damage it causes.