From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 47C91C433DF for ; Mon, 27 Jul 2020 19:10:12 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 0729320729 for ; Mon, 27 Jul 2020 19:10:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="U27QVmie" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0729320729 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:45380 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1k08Vn-0000AO-6X for qemu-devel@archiver.kernel.org; Mon, 27 Jul 2020 15:10:11 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:41038) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1k08V2-00088n-2H for qemu-devel@nongnu.org; Mon, 27 Jul 2020 15:09:24 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:34981 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1k08Uz-0007u6-JS for qemu-devel@nongnu.org; Mon, 27 Jul 2020 15:09:23 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1595876960; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=+L9bWD9Rp1zywQaxHNOfbEQdpKSZ/8gfiu5uLsraM9A=; b=U27QVmie3WWgVOQiVS/vMTD/z1zES50ef7v5phW7OjT+2gO66UmutGz2l11t4RX6wi3XVj 8eFu4fi5fKxd1omkL1KUPcHWQNVe4AR8RBVxT88q3IjGj5p3Ha5S3scRH5Om5cW8gR/pJQ wtJoX535c9UWzn5B8R2NkEh8vRxqEks= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-491-SdKztvAAOS-MGKkydDtRKw-1; Mon, 27 Jul 2020 15:09:13 -0400 X-MC-Unique: SdKztvAAOS-MGKkydDtRKw-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 9026058; Mon, 27 Jul 2020 19:09:12 +0000 (UTC) Received: from work-vm (ovpn-114-135.ams2.redhat.com [10.36.114.135]) by smtp.corp.redhat.com (Postfix) with ESMTPS id E45E270597; Mon, 27 Jul 2020 19:09:11 +0000 (UTC) Date: Mon, 27 Jul 2020 20:09:09 +0100 From: "Dr. David Alan Gilbert" To: William Lima Reiznautt Subject: Re: Live Migration (L2 network) Message-ID: <20200727190909.GA29172@work-vm> References: MIME-Version: 1.0 In-Reply-To: User-Agent: Mutt/1.14.5 (2020-06-23) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Received-SPF: pass client-ip=207.211.31.120; envelope-from=dgilbert@redhat.com; helo=us-smtp-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/07/27 15:02:33 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -30 X-Spam_score: -3.1 X-Spam_bar: --- X-Spam_report: (-3.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H3=-0.01, RCVD_IN_MSPIKE_WL=-0.01, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" * William Lima Reiznautt (willreli@gmail.com) wrote: > Hi folks, > > I hope everything is well. Hi, > Sorry about that doubt in this channel. No, it's the right place to ask! > I have a doubt about live migration interacting with layer 2 network, when > the live migration is running. How does the qemu signal the switch network > that the qemu instance changes port ? Because when the qemu migration to > another port switch, the switch has a time to understand that flow is > changed. > > I saw the dump traffic in live migration and I noticed that one packet > (RARP). "This packet is created by qemu." > > Does anyone know if there is documentation on this? I'm not sure we have documentation, but the code is in net/announce.c in recent qemu. When the migration has finished we send an ARP and then, when it starts running, we tell the guest to send a RARP; we send those a few times to make sure we don't miss it. Those are normally enough for the switch to realise that the VM has moved port; some very complex switch setups are less forgiving - in recent qemu's you can send the announce again later and/or change the timing of it. Dave > Thanks > > - - - > William Lima Reiznautt > willreli@gmail.com > www.ic.unicamp.br/~william -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK