From mboxrd@z Thu Jan 1 00:00:00 1970 From: ng0 Subject: Re: Network with QEMU generated image (guix system vm)? Date: Tue, 27 Sep 2016 20:14:21 +0000 Message-ID: <87wphxhzhe.fsf@we.make.ritual.n0.is> References: <87pont13rh.fsf@we.make.ritual.n0.is> <87a8exaw96.fsf@gnu.org> <87vaxlrqbf.fsf@we.make.ritual.n0.is> <8760plaulz.fsf@gnu.org> <878tuh2e25.fsf@we.make.ritual.n0.is> <87h9928t7j.fsf@gnu.org> <6b11e316-dc10-3575-adaa-4152e00b526d@rpapsch.de> Mime-Version: 1.0 Content-Type: text/plain Return-path: Received: from eggs.gnu.org ([2001:4830:134:3::10]:56185) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1boym5-000593-Ij for guix-devel@gnu.org; Tue, 27 Sep 2016 16:14:46 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1boym4-0001PR-BX for guix-devel@gnu.org; Tue, 27 Sep 2016 16:14:45 -0400 In-Reply-To: <6b11e316-dc10-3575-adaa-4152e00b526d@rpapsch.de> List-Id: "Development of GNU Guix and the GNU System distribution." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: guix-devel-bounces+gcggd-guix-devel=m.gmane.org@gnu.org Sender: "Guix-devel" To: Aljosha Papsch , Jan Nieuwenhuizen Cc: guix-devel@gnu.org Aljosha Papsch writes: > On 26.09.2016 19:30, Jan Nieuwenhuizen wrote: >> What I don't understand: sometimes the clone works instantly, sometimes >> I need to "wait a bit" until cloning or `ping gitlab.com' works. It >> seemed to be always immediately available when I added the mcron and >> rottlog test services, which confuses me even more. Might just be >> coincidence. >> >> Greetings, >> Jan >> > I'm guessing here but it sounds alot like neighbor discovery being slow > with ARP. I had the same issue few months ago with GNS3 where I created > a virtual topology. They use qemu VMs for each host. After creating > topology I wanted to ping a little and some packages would be dropped > before they went through. > > http://wiki.qemu.org/Documentation/Networking suggests in section > "Network backend types" that user networking is slow while tap > networking is fast. So ARP discovery performance might just suffer from > qemu user networking. Maybe it's worth trying tap networking. I used it > a few weeks ago (with lxc containers) and it's pretty flexible. Haven't > paid attention to performance though. Afaik gnunet uses tun/tap when available[0]. My limited knowledge about qemu I assumed that those modules in the way I can configure guix so far do not exist in the way I might want them in the vm (maybe) (different story, different problem). As far as my goals are concerned, this try and and error of something as simple as a stupid ping is slowing me down in developing guix services for my roadmap items. > I might be able to dig up notes on topology if you are interested. In > it, hypervisors form a VPN and integrate guests in the VPN using taps > and bridges. It's not a guix recipe unfortunately, just a Gnome Dia file. I'm very much interested, throw anything at me which helps me to solve this somehow. > Best regards > > [0] However, the lack of calling outside world is not gnunet exclusive. -- ng0