From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:55925) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YJ7mJ-0004us-Cx for qemu-devel@nongnu.org; Wed, 04 Feb 2015 16:46:32 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YJ7mG-000082-5d for qemu-devel@nongnu.org; Wed, 04 Feb 2015 16:46:31 -0500 Received: from mail-ob0-x234.google.com ([2607:f8b0:4003:c01::234]:61938) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YJ7mF-00007x-Vh for qemu-devel@nongnu.org; Wed, 04 Feb 2015 16:46:28 -0500 Received: by mail-ob0-f180.google.com with SMTP id vb8so3841753obc.11 for ; Wed, 04 Feb 2015 13:46:26 -0800 (PST) Received: from Gary.local (67-198-50-36.static.grandenetworks.net. [67.198.50.36]) by mx.google.com with ESMTPSA id mq8sm1363112oeb.2.2015.02.04.13.46.25 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 04 Feb 2015 13:46:25 -0800 (PST) Message-ID: <54D29330.8000605@gmail.com> Date: Wed, 04 Feb 2015 15:46:24 -0600 From: Gary R Hook MIME-Version: 1.0 References: <54D27AF1.8020302@redhat.com> In-Reply-To: <54D27AF1.8020302@redhat.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] Network Migration in QEMU during Live Migration List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org On 2/4/15 2:02 PM, Eric Blake wrote: > On 02/04/2015 12:01 PM, Azizul Hakim wrote: >> Does QEMU support network migration so that the migration process is >> transparent to users? For example if my VM has a web server, I would like >> my user still be able to send request to the server after the migration >> process is completed. But since migration causes a change of the physical >> machine, the IP address is different. So how do I achieve this? I >> understand that I've to create bridge network. What other things do I've to >> take care off? Is it possible at all? > > The IP address of the host is different, but the IP address seen by the > guest is the same. Live migration has been possible for several years > with qemu, and people do it all the time. The guest sees very minimal > downtime (a few milliseconds). If you use a higher-layer software, like > libvirt, then triggering a live migration of a guest is quite easy. What he said. The guest doesn't know, doesn't care, and doesn't change its network configuration; external connections are maintained. Only the host upon which the guest runs changes, and that is kind of irrelevant from a guest perspective. -- Gary R Hook Senior Kernel Engineer NIMBOXX, Inc