We are in the process of migrating this forum. A new space will be available soon. We are sorry for the inconvenience.

KVM and Bridging - How to make it work

2016-04-06, 01:00 AM
Hello All,

This is just a post to share how to get a KVM virtual machine to work using an additional or 'FailOver' IP address with bridging.

I'm posting this because I spent something like 10 hours beating my head against a wall, only to find out there was a single step left out of the instructions that makes ALL the difference.

http://docs.ovh.ca/en/guides-network-bridging.html is the link to setting up the bridging - and you should follow that.

BUT - in order to get it to actually work, you have to do one very important step.

Go to your 'Manage IP' screen in your dashboard, find the IP you are looking to use in your KVM guest, and click the gear next to it. Pick 'Add a Virtual Mac' and choose 'OVH' for the 'Type'

After a minute or two your mac address will appear on the screen. Make a note of this mac address (or keep it on your screen)

Now, go to your KVM host. Ensure your guest VM is shut down, then enter the following command.

sudo virsh virtualmachinename

where virtualmachinename is the name of your virtual machine from KVM. (You can see the names by doing

ls /etc/libvirt/qemu

Find the section with your network device. It should look something like this:

and change the mac address to match what shows for 'Virtual Mac' on your OVH dashboard.

That's it. Once you've switched this, you can save the file and start up your VM. From there, it should 'Just work'

Good luck all. Hopefully this saves someone else some hours and gray hairs.