Comment 1 for bug 1706705

Inspection of previous configuration values should be possible so that automatic removal of devices from bridges could occur when configuration changes; its made slight tricky that in order to restore the previous state, we also need to understand whether an ifdown/ifup cycle needs to be performed on the nic.

In terms of manually recovering from this problem - you should have been able to use:

  sudo ovs-vsctl del-port br-data eth0

which will remove eth0 as mapped to the br-data bridge back to the host OS.