Ubuntu 14.04 server: Change em1 to eth0 - no /etc/udev/rules.d/70-persistent-net.rules file

Question

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!

Solution

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:

GRUB_CMDLINE_LINUX_DEFAULT=""
GRUB_CMDLINE_LINUX=""

To:

GRUB_CMDLINE_LINUX_DEFAULT=biosdevname=0
GRUB_CMDLINE_LINUX=biosdevname=0

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.

Comments

[lchristina26]

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?

[Audioz]

Try sudo apt-get install biosdevname and then run sudo update-initramfs -u

[lchristina26]

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

[Audioz]

And this is after you ran sudo apt-get install biosdevname and then sudo update-initramfs - u ?

[lchristina26]

Yes. Do I need to reboot after running sudo update-initramfs - u and then do ```sudo update-grub`` and reboot again?

[Audioz]

Yes, you'll need to reboot after installing biosdevname and updating the initramfs

[Audioz]

Let us continue this discussion in chat.

[lchristina26]

This solution worked, thanks John Jensen!