Predictable network interface names re-enabled after update on server image

[James]

Hello...

We're working with the 16.04 Server (minimal) image here. After initial install, predictable network interface names are disabled as advertised. However, after doing an apt update/upgrade, they return (I'm guessing) do to the recent systemd update.

I see /boot/cmdline.txt still contains "net.ifnames=0 biosdevname=0", but it doesn't seem to have any effect. I've disabled them again by adding an entry via /etc/udev/rules.d/70-persistent-net.rules.

I just tested this with a fresh image, booting to verify eth0, then apt update/upgrade and reboot to see eth0 removed and an enx------------ mac based interface in its place.

Thanks!

[Ricardo (gizmotemp)]

Hello,
after some digging I found the origin of the "problem"

When you make apt-get update/upgrade you will update some packages and one of that packages is the udev.

After the update of udev, it updates the file /lib/udev/rules.d/73-special-net-names.rules adding the following line:
ACTION=="add", SUBSYSTEM=="net", SUBSYSTEMS=="usb", NAME=="", ATTR{address}=="?[014589cd]:*", IMPORT{builtin}="net_id", NAME="$env{ID_NET_NAME_MAC}"

If you comment this line everything will work as before!

[Danilo Falcão (fcon)]

Commenting the line worked for me. +1

[Alistair Buxton (a-j-buxton)]

The line no longer exists in that file. It is in 73-usb-net-by-mac.rules. Commenting it makes no difference. Not surprising since it is surrounded by a check against net.ifnames=0. But this bug still happens after upgrading the system.

[Alistair Buxton (a-j-buxton)]

FWIW I'm using the official image, not the one made by the flavour maker.

[James (k-james-d)]

May not be the "best" answer, but I'm just adding /etc/udev/rules.d/70-persistent-net.rules with the following:

SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{dev_id}=="0x0", ATTR{type}=="1", KERNEL=="eth0", NAME="eth0"

And not touching changes made by that packages.

[Simon Marchi (simon-marchi)]

I built a 16.04 minimal image from the scripts, and had this behaviour too (predictable interface name enabled). Creating the link as follows (and rebooting) reverted to eth0:

  ln -s /dev/null /etc/udev/rules.d/80-net-setup-link.rules

Source: https://www.freedesktop.org/wiki/Software/systemd/PredictableNetworkInterfaceNames/

[Tim Jardim (tcjx14me)]

@James Pooton

Your suggestion is the one that worked for me
adding /etc/udev/rules.d/70-persistent-net.rules with the following:
SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{dev_id}=="0x0", ATTR{type}=="1", KERNEL=="eth0", NAME="eth0"

The other suggestions did not work for me.

- The name change is more of a nuisance than anything. bringing the adapter up and either requesting a new IP via DHCP or assigning a static IP will also work. Changing functional scripts would be a pain however.

Thanks again all
Tim Jardim

[Shuhao (shuhao)]

I find that adding the /etc/udev/rules.d/80-net-setup-link.rules file does in fact work. However, the system hangs during boot when not plugged into to ethernet.

[nikolka-kapustin (nikolka-kapustin)]

The same issue for me. Another topic for rasp forum:https://www.raspberrypi.org/forums/viewtopic.php?f=28&t=23400