Ethernet tethering / not working, no IP address assigned

/e/OS Devices Fairphone
1

I have Fairphone 5, with /e/OS 3.0.4-t-20250709507786-official-FP5 installed

Hotspot via Wifi is working: The client receives per DHCP an IP address and can connect to the internet.

However, when using Ethernet tethering, the option is visible and I can enable it, but after that, my PC does not get an IP address assigned. Although the PC network interface is configured to use DHCP.

The USB-C to Ethernet adapter is the following: Delock 66644 (Gigabit LAN Adapter with additional USB-C connection to charge/power the phone simultaneously.)

I use Ubuntu 24.04 and the network interface uses DHCP.

So does anyone knows how to solve this? Why does the mobile phone not assign an IP address? How can one troubleshoot this?

If a static IP address should be assigned, which is it?

Alternatively, I also tried a belkin USB-C to ethernet adapter F2CU040. This adapter is also recognized, but also does not receive an IP address.

Thanks in advance for any help.

Regain your privacy! Adopt /e/OS the deGoogled mobile OS and online servicesphone

2

Have you tried a USB-C to USB-C data-cable?

Most computers will then recognize the USB-connection as a NIC/network interface.

Have a nice evening :slight_smile:

3

Would one of your adapters possibly require a crossover cable? Most modern do not, but thought I would ask.

I have used the USB-C to USB-C from a e/os Fairphone 4 to an Iode device, and that worked as @ludensen mentioned.

4

With a USB-C to USB-C cable, I can use the RNDIS virtual Ethernet connection and with that, my PC gets an IP address.

But I need a real Ethernet Interface to make a pfsense router work from within its WAN Ethernet connection. And before connecting it to my pfsense router, I just want to make sure DHCP works on the Ethernet connection and that’s why I test it on a PC.

The Ethernet interface is auto sensing, so without a cross-over cable it should work. But I did test to see if an Ethernet switch in between would be different.

Has anyone had success with using Ethernet Tethering on an FP5 ?

5

try this:
Using an Android phone
Log in to phone
Attach phone to PC with USB cable
Open (phone) settings > Network & Internet > Data Saver disabled > Hotspot & tethering > USB tethering enabled

Open (PC) Gnome settings > Network > USB ethernet should be connected.

Thanks to a person named: tea-for-one

6

As I mentioned above, I’m on a FP4. I just tested what you are attempting, and did get it to work. But, I had to swap my USB-C adapters.

On my first attempt, my FP4 would not recognize my UGreen 2.5Gbe adapter. It’s a RTL8156BG chipset.

So I swapped to older 1Gbe adapter (RTL8153). The FP4 recognized it, allowed me to turn on the Ethernet Tether toggle, and my laptop received an IP. I’m actually updating this post on that connection.

My laptop in PopOS 22.04, and it recognizes both.

Not recognized on FP4
https://www.amazon.com/dp/B0CD1FDKT1?ref=ppx_yo2ov_dt_b_fed_asin_title

Recognized on FP4
Realtek Semiconductor Corp. RTL8153 Gigabit Ethernet Adapter

7

@Jets Thanks, I know it is working with a USB-C (to USB-C) cable, since I tested that with success. However, the option to enable Ethernet tethering is available in the “Hotspot and tethering” settings and I need specifically that option in my use case. It is just that, if there is anyone on a FP5 who can confirm that it is working with Ethernet tethering that would confirm that the problem is somewhere else.

8

@xancudo Thanks! The Delock 66644 has the RTL8153 chipset as well and because the “Ethernet tethering” option is selectable, I assume the Kernel from my FP5 supports that chipset as well. It is just that it does not provide an IP address to the PC.

With Wifi tethering and USB tethering it works as expected.