Loopback address missing in Ubuntu 14.04 (KVM)

Instantiating a new VM from KVM/Ubuntu 14.04 results in a loopback interface without any address after startup:

root@nico:~# ip addr show lo
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
root@nico:~# ifup lo
ifup: interface lo already configured

Anyone an idea, why this is happening?

Hi Nico.

i think is a problem at Ubuntu… i dont use ubuntu, but quick patch can be edit the /etc/network/interfaces and set that:

> auto lo
> # iface lo inet loopback
> iface lo inet static
> address
> netmask

Yes, isnt the clear (and clever) option… but my knows about Ubuntu are so bad :frowning:

It seems to be related to a trusty 14.04 bug:



yes, it seems… but do you test option? its may work until a patch by ubuntu.

@alfeijoo I will give that workaround a try - but the real problem is that any VM coming up within opennebula and ubuntu 14.04 suffers the missing ip problem

1 Like


but if you instantiate one, change it (look that lo interface its always the same) and after upload to your datastore and make it public (or in your marketplace if have)

hope ubuntu solve that bug.

I would actually LOVE to publish a modified version - we have requested access to the marketplace MONTHs ago, but have never been granted access (as ungleich GmbH)

Hi Nico,

The ungleich account is enabled, if you have any problems logging in the marketplace just write me an email to dmolina@opennebula.org.


There is no updated package that fixes the problem. There is one for utopic but not for trusty (irony).

I’ve managed to make the loopback work adding a script in /etc/one-context.d/06-loopback that contains:

ifconfig lo

Make sure to make the script executable. You can do it easily without starting the VM using guestfish. Something like:

# guestfish -ia image.qcow2
> touch /etc/one-context.d/06-loopback
> vi /etc/one-context.d/06-loopback
> chmod 0755 /etc/one-context.d/06-loopback
> quit

If you do it starting the VM make sure to clean the configuration before shutting down in the following places:

  • /etc/network/interfaces
  • /root/.ssh/*
  • /etc/resolv.conf

The upload speed from my current connection is really slow so I can not update the image. I’ll do it from the office next week.

I’ve just changed the Ubuntu 14.04 image with the script that sets the loopback IP.


That’s great, thanks a lot!

Please tell - should this image work with Opennebula 4.12.1 KVM?

Answered in Opennebula 4.12.1 KVM DEPLOY FAILURE

The image works in OpenNebula 4.12 but I’ve messed up and uploaded an image not compatible with qemu < 1.1.

Thanks, I used older image, as you advised.

I’ve just updated the Ubuntu 14.04 image with the correct format.