Setting network interface name via udev rules

[btkostner]

Hello everyone 👋

I'm currently running Talos on a cluster of various Intel NUCs running Cilium. Due to some configurations options, I need all of the interface names to be the same. I have tried to achieve this with udev rules set in the configuration like so:

machine:
  udev:
    # Rename all Intel NUC network devices to net0 for consistency
    # required for Cilium configuration. Hardware addresses are taken
    # from the output of `talosctl get links`.
    #
    # Note: currently this does not work
    rules:
      - SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="88:ae:dd:0e:a9:39" ATTR{type}=="1", NAME="net0"
      - SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="48:21:0b:2e:2b:6c" ATTR{type}=="1", NAME="net0"
      - SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="1c:69:7a:aa:4a:db" ATTR{type}=="1", NAME="net0"
      - SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="1c:69:7a:60:69:20" ATTR{type}=="1", NAME="net0"

Sadly running this causes this to show up in dmesg:

192.168.3.12: user: warning: [2023-12-01T17:16:27.419532224Z]: [talos] task writeUdevRules (1/1): starting
192.168.3.12: daemon:     err: [2023-12-01T17:16:27.451923224Z]: udevd[2662]: Error changing net interface name enp89s0 to net0: Resource busy
192.168.3.12: daemon: warning: [2023-12-01T17:16:27.454487224Z]: udevd[2662]: could not rename interface '8' from 'enp89s0' to 'net0': Resource busy
192.168.3.12: user: warning: [2023-12-01T17:16:27.563055224Z]: [talos] task writeUdevRules (1/1): done, 143.517169ms

I've also tried to rewrite some of the built in udev rule files with no success.

Has anyone been able to rename network devices consistently?

[smira]

The udev user rules are applied "too late", at this time Talos network stack is already running and opening the links. You might be able to workaround this by making the links ignored in the machine config/kernel args, but I'm not sure.

You can also disable predictable interface naming with net.ifnames=0.

[btkostner]

Noted. I've tried disabling the predicted interface naming but I'm still unable to get everything with the same interface name. I'll try using the ignored work around and report back. Thank you!

[btkostner]

Seems like using ignore: true and trying to manually rename the interface with udev rules results in no network configuration and failing to bootstrap the cluster, so that won't work. I'll keep trying some hacky solutions and see if I can get this to work.

[timtorChen]

Just run into the same issue while installing Talos v1.6.4 on a clean NUC11.
For my case, adding the kernel parameter net.ifnames=0 works.
Is the parameter appeared in /proc/cmdline?

[btkostner]

I've worked around this issue on the Cilium side of things, so I don't have a node to test this on right now. Is there a way to read /proc/cmdline without networking?