From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:48519) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z2H0m-0000i4-7W for qemu-devel@nongnu.org; Tue, 09 Jun 2015 06:44:05 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Z2H0f-0001EX-QK for qemu-devel@nongnu.org; Tue, 09 Jun 2015 06:44:04 -0400 Received: from mail-wi0-x236.google.com ([2a00:1450:400c:c05::236]:37398) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z2H0f-0001E0-Ki for qemu-devel@nongnu.org; Tue, 09 Jun 2015 06:43:57 -0400 Received: by wifx6 with SMTP id x6so11964786wif.0 for ; Tue, 09 Jun 2015 03:43:56 -0700 (PDT) Date: Tue, 9 Jun 2015 11:43:54 +0100 From: Stefan Hajnoczi Message-ID: <20150609104354.GD27900@stefanha-thinkpad.redhat.com> References: <55701BED.2090802@redhat.com> <1433510652-13866-1-git-send-email-thibaut.collet@6wind.com> <55752E3C.8070700@redhat.com> <20150608133203.GM23825@stefanha-thinkpad.redhat.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="LKTjZJSUETSlgu2t" Content-Disposition: inline In-Reply-To: Subject: Re: [Qemu-devel] [PATCH v2] net: Add support of VIRTIO_NET_F_GUEST_ANNOUNCE for vhost-net/vhost-user List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Thibaut Collet Cc: Jason Wang , Juan Quintela , qemu-devel , Stefan Hajnoczi , "Michael S. Tsirkin" --LKTjZJSUETSlgu2t Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Jun 08, 2015 at 05:32:38PM +0200, Thibaut Collet wrote: > > 3. The easiest solution - nop .receive() >=20 > The solution 3 is similar of my implementation and does not solve issue > pointed by Jason: legacy guest do not send a gratuitous ARP. Yes, but it prints a warning so the user is aware they are operating in a degraded state. Sending gratuitous ARP packets minimizes the time that network infrastructure forwards packets to the old host. But the network infrastructure will learn about the new host as long as the guest sends outgoing packets after migration. Putting these two things together, it seems acceptable to do #3. Most users should be running a modern virtio-net that supports the announce feature anyway. Stefan --LKTjZJSUETSlgu2t Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQEcBAEBAgAGBQJVdsNqAAoJEJykq7OBq3PI2twH/1zwcNQMZn2MneAEnym9USNz CFgbleo6mFc9q7KBdy1DuGdsgTXvrsQ59tkWsKnT/LFN6yCoAt+aI0hEE5b9f5cl zPfSfJDD3sPnJz704yE9cyn7Ykp/HfZoKUxH3oNzU2cxwuB8cVNI+wQnADb07Kub nHJXBlXmKXFGktc1ykqTHgE+yy1YmY6DmkTE2HDCzxOSE6ouEmOhugY+3ur+cYtF WoiV3zHGGG2e0wEqlk3EH+/5cQLcAi6cXCF2GaF/VMWitUU2zNF2gPcUyVMmkE5m JZ2kWpeE1N226ullOFlBh48zyyHieRl5p5mZI7T1ynoyvQhv2+NtxMm9PFx3YQk= =3/cJ -----END PGP SIGNATURE----- --LKTjZJSUETSlgu2t--