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USB3 ethernet adapter not working?

Posted: 2020/10/08 18:56:34
by gcomes
Hi,
on a Dell laptop (XPS 15 7590) I have installed CentOS 8.2. Like all recent laptops, it doesn't have a ethernet port and it is necessary to use a usb ethernet adapter. However none seems to work.
I have tested:
USB3 Realtek RTL8153 Gigabit Ethernet Adapter (0bda:8153) kernel driver r8152
USB3 ASIX Electronics AX88179 Gigabit Ethernet (0b95:1790) kernel driver ax88179_178a
They do not work. Once plugged, the kernel sees them, a network interface is created, once I plug the network cable the output of the command 'ip link' doesn't show anymore the flag <NO-CARRIER>. And that's it. The network interface never get an IP address.
The only adapter I got working is a USB1 Realtek adapter (0bda:8050) kernel driver r8152.
The problem is not the laptop hardware. On the same laptop all the adapters used to work on openSUSE 15.1 (kernel 4.12)
It looks to me like there is something missing in the CentOS 8 kernel configuration.
Any suggestion?
Thanks.

Re: USB3 ethernet adapter not working?

Posted: 2020/10/16 13:51:16
by gcomes
Update.
The problem is not with the ethernet adapter itself. I found a working USB3 ethernet adapter with the same chip as the one that was failing. The hardware difference between the working one and the not working one is that one is a simple network adapter, the other is a four port hub with one port being the network adapter. So connecting a USB network adapter to an external HUB did not work.
However I manage to find the source of the problem and fixed it.
The trouble is introduced by the package: NetworkManager-config-server
More precisely the line:
no-auto-default=*
in /usr/lib/NetworkManager/conf.d/00-server.conf
Removing NetworkManager-config-server or commenting the such line fixed the problem for me.