This is tracking the upstream effort needed to deliver the feature request described below.

What's the feature?

Currently ovn-controller only supports a single value (IPv4 OR IPv6) for the per-chassis ovn-evpn-local-ip configuration. This value is used as the local-ip for the VXLAN tunnel flows ovn-controller configures for EVPN enabled switches.

From our ovn-controller man page:

      <dt><code>external_ids:ovn-evpn-local-ip</code></dt>
      <dd>
        IP address used as a source address for the EVPN traffic leaving this
        OVN setup. There is currently support only for single IP address
        being specified. NOTE: this feature is experimental and may be subject
        to removal/change in the future.
      </dd>

Also in the upstream TODO file:

  * Allow ovn-evpn-local-ip to accept list of
    $VNI1:$LOCAL_IP1,$VNI2:$LOCAL_IP2 combinations which will be properly
    reflected in physical flows for given LS with VNI.

Why is it needed?

Dual-stack deployments (IPv4 + IPv6) are a common thing. It's necessary to support dual-stack before we can promote the EVPN OVN support to "fully supported" from "experimental".
 

Who will benefit? 

All potential users of the OVN EVPN native support (e.g., ovn-kubernetes or neutron).