Subject: Re: [PATCH net-next v2 6/6] vxlan: allow multiple VXLANs with same VNI for IPv6 link-local addresses

From: Stephen Hemminger <[email-masked]>
Date: Fri, 14 Apr 2017 10:38:30 -0700

On Fri, 14 Apr 2017 18:44:46 +0200
Matthias Schiffer <mschiffer-Nyw9WiXk/[email-masked]> wrote:

> As link-local addresses are only valid for a single interface, we can allow
> to use the same VNI for multiple independent VXLANs, as long as the used
> interfaces are distinct. This way, VXLANs can always be used as a drop-in
> replacement for VLANs with greater ID space.
> 
> This also extends VNI lookup to respect the ifindex when link-local IPv6
> addresses are used, so using the same VNI on multiple interfaces can
> actually work.
> 
> Signed-off-by: Matthias Schiffer <mschiffer-Nyw9WiXk/[email-masked]>

Why does this have to be IPv6 specific?

What about the case where VXLAN is not bound to an interface?
If that is used then that could be a problem.