# Revision history [back]

### Confused About neutron_external_interface

Hello,

About this neutron_external_interface in etc/kolla/globals.yml the following is stated:

This is the raw interface given to neutron as its external network port. Even though an IP address can exist on this interface, it will be unusable in most configurations. It is recommended this interface not be configured with any IP addresses for that reason.

https://github.com/openstack/kolla-ansible/blob/master/etc/kolla/globals.yml#L81-L85

I'm trying to figure out how I'm supposed to interpret this in terms of how I can actually implement this to get my instances online.

At the moment I have a multinode setup with a controller and a compute node. I've used kolla-ansible to deploy. I have 2 interfaces on each host, ens2f0 and ens2f1. The ens2f0's are the external public interfaces with public IP addresses. The ens2f1's are the internal interfaces and have an RFC 1918 address on.

Looking at what it says I guess I'm not supposed to just make the neutron_external_interface the ens2f0? I actually tried this and it broke connectivity to the compute node I think. So am I supposed to make a loopback or bridge interface and use that, or what?