Comment 3 for bug 1874418

We create an external ("public" network) interface on undercloud:
https://github.com/openstack/tripleo-quickstart-extras/blob/master/playbooks/prepare-slave.yml#L37-L45
network_config:
    - type: interface
      name: eth2
      use_dhcp: false
      mtu: 1450
      addresses:
        - ip_netmask: 10.0.0.1/24
        - ip_netmask: 2001:db8:fd00:1000::1/64

when we create extra node with OVB, we receive for it DHCP from public network and sometimes it allocates 10.0.0.1 for it, which overlaps with manual set undercloud eth2 above.

So there are possible solutions:
1) to set manually hardcoded IP for extra node in OVB template
2) to remove 10.0.0.1 from allocation pool of public network in OVB stack