I am currently trying to get a grip on vnuml ( http://www.dit.upm.es/vnumlwiki/index.php/Tutorial ) which has good howtos and tutorial for building host- and uml- kernels and root_fs. Especially vnuml offers a framework for virutal network configuration based on xml-configuration files. I think texas-kernel is also patched for vnuml enhancements but for texas's root_fs and network-configuration scripts I am not shure. Maybe aaron can provide some more background on that? In order to releas texas from unproductive trial-and-error configuration testing (and feeling less intervening when applying core-kernel-patches or installing new system-libraries) I started to setup a small vnuml environment on my home-pc. Therefore I found also the following links quite useful: http://www.dit.upm.es/vnumlwiki/index.php/Installation http://www.enic.fr/people/landru/viminal/vnuml.gentoo/how-to/vnuml-gentoo-g… ( gentoo oriented setup, host-kernel-enhancement, uml-kernel, root_fs ) http://www.dit.upm.es/vnumlwiki/index.php/Howto ( further links for root_fs howtos ) @aaron: do you have a link explaining from-scratch busybox-based uml-rootfs generation (as being used on texas) ? ciao, axel On Saturday 09 June 2007 01:07, Benjamin Henrion wrote:

On 6/9/07, Aaron Kaplan <aaron(a)lo-res.org> wrote: Yes, as far as I remember, vnuml needs a lot of things in order to work... well, things that all linux distros usually have, but not busybox. It was something like ... install its boot scripts in the vnuml'd system, make it mount an fs on the host, then use ssh for something and so on and so on. But the biggest problem we had was actually... that it was constantly making our poor system crash. Anyway, I guess we just had to drop it in order to move on. I do believe there are some nice things about vnuml, but ... Briefly, the olsr_switch works like this: in olsrd, there is this special 'driver' that doesn't use a netif for transmission, but a tcp connection instead. that connection goes to the olsr_switch. Also, there are some patches preventing all instances to modify the same routing table. So, in order to make batman work with olsr_switch (or whatever) I guess modifications might be needed. There is also an N-th way of doing it, probably: pseudo interfaces (like tap) instead of tcp connections. Nevertheless, all batmans (or olsrds) will share the same routing table. --- Yes, there is - ::1, only bigger ;)

On 6/10/07, zethix or something &lt;zethix(a)gmail.com&gt; wrote: What about using OpenVZ instances (each instance has its own TCP IP stack I think)? I did not manage to have a working 32bit UML kernel+busybox rootfs for testing OLSR and/or batman (ifconfig did not work out with the busybox rootfs version of http://uml.nagafix.co.uk/BusyBox-1.5.0/BusyBox-1.5.0-x86-root_fs.bz2 and kernel version vmlinux-2.6.18.1-bb2), if someone can recommend me one version for each of those. -- Benjamin Henrion <bhenrion at ffii.org> FFII Brussels - +32-484-566109 - +32-2-4148403

Hello, We have used OpenVZ (linux-2.6.18-openvz-028.035.1) for emulating batman and olsr. Further background information about the setup is given here: http://open-mesh.net/batman/doc/evaluation/setup-details and about the general evaluation methodology here: http://open-mesh.net/batman/doc/evaluation Not yet documented but: Recently also managed to run openVZ (with many virtuaized debian systems) inside of qemu-kvm. Used this for proof of concept, testing and performance evaluation. This has the advantage of: - having all relevant data in a qemu image. - The image could be easily transferred to another machine (actually Iam waiting to move it to texas). - could be easily backupped - Any misconfiguration inside qemu does never harm your real system !! The following worked: - On 2GHz core duo notebook (qemu using only one processor and 800MB Ram) - More than 100 virtual instances idling in parrallel - About 60 virtual instances running olsr or batman in parrallel - use brctl, ebtables, TC, and NETEM for configuring virtual networks with - dedicated links - dedicated packetloss, delay for unicast and broadcast traffic - Having all the tools like wireshark, tcpdump, ... for network monitoring,. - Being able to monitor all virtualized VZ processes from the qemu system. If somebody is interested in using or even helping to document and extend that system, would be really appreciated. ciao, axel On Montag 01 Oktober 2007, Aaron Kaplan wrote:

Hello On Dienstag 09 Oktober 2007, Benjamin Henrion wrote: [snap] [snap] If you follow the link in the above lines, you will find a line like: ... patched again to fix a bug in the ebtables part of the 2.6.18 kernel extracted from patch-2.6.18.8 from http://www.kernel.org/pub/linux/kernel/v2.6/ and downloadable here... Why not having a look ?

Hello, As fare as I remember there have been some promlems with the development versions of openVZ. With the stable version for kernel 2.6.18 everything worked fine. Except, the ebtables module oopsed when applying more than 25 rules !! Because I wanted to configure virtual networks with up to 100 nodes this was a problem. The mentioned patch solved this problem. ciao /axel

Aaron Kaplan &lt;aaron(a)lo-res.org&gt; [071009]: Many = which number? I have started 10 of those, and it works fine on a 1500Mhz machine with 512MB of RAM on a livecd system with minimal debian filesystems on a harddisk. -- Benjamin Henrion &lt;bhenrion(a)ffii.org&gt; FFII Brussels - +32-484-566109 - +32-2-4148403

On Die, 2007-10-09 at 16:56 +0200, Aaron Kaplan wrote: There should be much more possible since olsrd uses way less (> 30% or so) CPU time (and probably RAM - no one ever measured that AFAIK really. But Hannes killed code and lots of malloc()s/free()s) than 3 months ago. As for Vserver: Yes, that might be another trial worth (especially if the vservers 99% identical) but AFAIK it needs a patched kernel. And "Vserver on UML": Herbert should know better if one can mange to run that. At least playing around is less risky. Bernd -- Firmix Software GmbH http://www.firmix.at/ mobil: +43 664 4416156 fax: +43 1 7890849-55 Embedded Linux Development and Services