From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:43295) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gUasW-0004ok-H1 for qemu-devel@nongnu.org; Wed, 05 Dec 2018 12:22:29 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gUasR-0007RX-H7 for qemu-devel@nongnu.org; Wed, 05 Dec 2018 12:22:28 -0500 Received: from mx1.redhat.com ([209.132.183.28]:39406) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1gUasR-0007QI-Ac for qemu-devel@nongnu.org; Wed, 05 Dec 2018 12:22:23 -0500 Date: Wed, 5 Dec 2018 12:22:18 -0500 From: "Michael S. Tsirkin" Message-ID: <20181205121914-mutt-send-email-mst@kernel.org> References: <20181025140631.634922-1-sameeh@daynix.com> <154402670926.16620.2184992513838364109@sif> <20181205170916.GK799@angien.pipo.sk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181205170916.GK799@angien.pipo.sk> Subject: Re: [Qemu-devel] [libvirt] [RFC 0/2] Attempt to implement the standby feature for assigned network devices List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Peter Krempa Cc: Michael Roth , Jason Wang , QEMU Developers , Sameeh Jubran , Yan Vugenfirer , libvir-list@redhat.com, Eduardo Habkost On Wed, Dec 05, 2018 at 06:09:16PM +0100, Peter Krempa wrote: > From managements point of view, bundling all this together is really not > a good idea since it creates a very big matrix of failure scenarios. I think this is clear. This is why we are doing it in QEMU where we can actually do all the rollbacks transparently. > In > general even libvirt will prefer that upper layer management drives this > externally, since any rolback scenario will result in a policy decision > of what to do in certain cases, and what timeouts to pick. Architectural ugliness of implementing what is from users perspective a mechanism and not a policy aside, experience teaches that this isn't going to happen. People have been talking about the idea of doing this at the upper layers for years. -- MST