My internet connection is off the ethernet port of a PCI-E card that also has USB ports on it, so the ethernet device is recognized as a "USB ethernet device"...
Back in Debian Buster, I learned that the "predictive" naming of this USB ethernet interface would be governed by "73-usb-net-by-mac.rules" and so I had it configured accordingly with a config file in /etc/network/interfaces.d/... Namely that the device name would basically be its MAC. Well, I just upgraded to Bullseye, and I can't bring up the darn interface. I have tried fiddling around with the device name in my config file in /etc/network/interfaces.d/ directory, but it just won't come up. The Networking.service also fails during bootup. I also noticed that the 73-usb-net-by-mac.rules file has completely disappeared, never mind that the official Debian NetworkInterfaceNames page here <https://wiki.debian.org/NetworkInterfaceNames> still talks about it! Anyone know how the heck this is supposed to work in Bullseye? BTW, the device shows up as disabled in lshw (I obfuscated the MAC in the output): *-network DISABLED description: Ethernet interface physical id: 1 bus info: usb@7:1 logical name: enx00XXXXXXXXXX <<<=== Yes, I tried using this name in the config serial: 00:XX:XX:XX:XX:XX size: 10Mbit/s capacity: 1Gbit/s capabilities: ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd 1000bt 1000bt-fd autonegotiation configuration: autonegotiation=off broadcast=yes driver=ax88179_178a driverversion=5.10.0-11-amd64 duplex=half link=no multicast=yes port=MII speed=10Mbit/s
