[ovs-discuss] Geneve and IPv6

[Ben Pfaff]

On Thu, May 10, 2018 at 05:54:30PM -0700, Gregory Rose wrote:
> On 5/1/2018 6:53 PM, Ben Pfaff wrote:
> >Hi Greg.
> >
> >We've had multiple reports now that Geneve kernel-based tunnels do not
> >work in Open vSwitch if IPv6 is not enabled.  Do you have an idea
> >whether we should consider this a bug in OVS or a bug in the
> >documentation?  That is, should we plan to fix it (when we can) or
> >should we plan to document that Geneve requires IPv6?  (Or is something
> >else going on?)
> >
> >No rush.
> >
> >Thanks,
> >
> >Ben.
> 
> Sorry for the late response.  It is just how the Linux kernel is
> configured.  There was an internal bug
> filed a few months ago where I found that geneve depends on a certain kernel
> configuration that
> cannot be overridden and disabling ipv6 causes the check for the
> configuration to always fail.
> 
> The upshot is that there is no fix without making changes to the upstream
> Linux kernel.  It is a Linux
> kernel limitation and should probably be documented as you say, i.e. "Geneve
> requires ipv6".

Thanks for investigating.

Even if this isn't fixable out-of-tree, is it something for which we
should submit a fix so that future upstream releases don't have the same
limitation?

Thanks,

Ben.