Re: [PATCH 0/4 for 2.3] vhost-user live migration support

[Peter Xu <peterx@redhat.com>]

On Tue, Dec 15, 2015 at 04:23:24PM +0800, Yuanhan Liu wrote:
> On Mon, Dec 14, 2015 at 11:58:42AM +0800, Peter Xu wrote:
> > If ping to guest from outside, when the migration finishes on the
> > target side of qemu, qemu_self_announce() will be called.
> 
> It's supposed to see some ARP requests if I run tcpdump against
> with the ovs bridge, right? However, in fact, I saw nothing from
> tcpdump on the target host when the migration is done.
> 
> I mean I do find that qemu_annouce_self composes an ARP
> broadcoast request, but it seems that I didn't catch it on
> the target host.
> 
> Something wrong, or someting I missed?

AFAIK, it should be RARP rather than ARP request. However, sorry
that I do not know the reason for its lossing either.

Btw, I did a very basic live migration using v1 patchset locally
today (one host, two QEMU instances attach to the same vhost-user
socket), it's working too on my host. :)

Thanks.
Peter

> 
> 	--yliu
> 
> > Although
> > we might see a warning like "Vhost user backend fails to broadcast
> > fake RARP" (notify is done by hacking vhost_user_receive(), even if
> > notify fails, things will still move on), QEMU should still send a
> > RARP onto the link.
> > 
> > Not sure whether I missed anything.
> > 
> > Thanks.
> > Peter