I am trying to rename one of my network interfaces from em1 to eth0. I do not have /etc/udev/rules.d/70-persistent-net.rules. I have tried to regenerate this file by running these commands:

udevadm trigger
udevadm trigger --action=add
udevadm trigger --action=change

I tested each command individually, rebooted, looked for the 70-persistent file, before trying the next. None of the commands work, as the file is still not there, even after reboot.

I have also tried manually running the /lib/udev/write_net_rules and I get this error:

Cannot lock /etc/udev/rules.d/70-persistent-net.rules!

This is what is in my /etc/network/interfaces file (nothing else):

auto lo
iface lo inet loopback

My ifconfig output results in no eth0 interface, but I have an em1 interface that I need to change to eth0. I don't know how to do this without re-creating the 70-persistent file. Any help in either recreating this file or changing em1 to eth0, or both, would be greatly appreciated!


1 Answer 1


EDIT: After a small troubleshooting session with OP I'm modifying the answer to remove the quotes for "biosdevname"

Edit the following lines in /etc/default/grub:




Next, run sudo update-grub and then reboot.

After this, you should have the udev rules persisted in /etc/udev/rules.d/70-persistent-net.rules and you can edit them as necessary.

Make sure you're changing the right interface by comparing MAC address information properly, e.g. via ifconfig -a.

  • When I add that to grub and run sudo update-grub I get the error: biosdevname=0: not found. Am I missing a package or other file? Aug 17, 2015 at 16:53
  • Try sudo apt-get install biosdevname and then run sudo update-initramfs -u Aug 17, 2015 at 16:55
  • That did not work, I still get the same error. In full it is : /usr/sbin/grub-mkconfig: 12: /etc/default/grub: biosdevname=0: not found Aug 17, 2015 at 18:30
  • And this is after you ran sudo apt-get install biosdevname and then sudo update-initramfs - u ? Aug 17, 2015 at 19:20
  • Yes. Do I need to reboot after running sudo update-initramfs - u and then do ```sudo update-grub`` and reboot again? Aug 17, 2015 at 19:34

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .