How to bridge KVM VMs onto physical network

The default bridge on KVM is 192.168.122.1/24.

We’re going to create a bridge to allow VMs to have an IP on your physical network.

1. Create a bridge br0

   nmcli con add ifname br0 type bridge con-name br0
   

2. Now we’re going to enslave br0 to the interface with an appearance on the network you want to glom onto. In my case it’s enp7s0f0:

   nmcli con add type bridge-slave ifname enp7s0f0 master br0
   

3. Trust but verify

   nmcli connection show
   

4. Flop any IP you had on the old MAC to the new generated br0 MAC.

5. Make a file called br0.xml somewhere (anywhere) that has this in it:

   <network>
   <name>br0</name>
   <forward mode="bridge"/>
   <bridge name="br0" />
   </network>
   

6. Run these virsh commands to define the network:

   virsh net-define /tmp/br0.xml
   virsh net-start br0
   virsh net-autostart br0
   virsh net-list --all