The hotel we are staying in for FOSDEM is providing an expensive wireless access limited to 15kB/s.

For a faster access the solution is to use IP-over-DNS for a rate up to 48kB/s. Moreover it's free...

Wouter, I really doubt that the decision of having a Xen build daemon has been taken in a team, and the fact is that it's causing problems.

The only goal of my post is to show we have double standards.

There has been a few flam\^Wdiscussions about emulated build daemons, each time coming to the conclusion that we should not upload packages built on an emulated machine to the archive.

However Debian has started to use at least one paravirtualized (Xen) build daemon, the i386 experimental one. The result is that one of the tests of the GNU libc testsuite is failing. On the other hand, the GNU libc and the GCC testsuites are giving the same results on a QEMU emulated machine and a real machine, for amd64, arm, armel, i386, mips, mipsel and powerpc. Same for KVM on amd64 and i386.

I wonder if we made the right choice ...

For a few weeks Laurent Vivier, Blue Swirl and myself have been working on getting QEMU PowerPC working correctly with recent distributions.

QEMU used to rely on OpenHackWare for the OpenFirmware implementation on PowerPC. It is a very limited implementation (for example it as no Forth support), which is unable to boot most 2.6.x kernels with the OldWorld emulation. It is able to boot recent kernels with the PReP emulation, but things like the PCI bus emulation are not working correctly. Moreover the PReP kernels are gone with the removal of the arch/ppc tree.

OpenBIOS was already used for the OpenFirmware implementation of Sparc 32 and Sparc 64 targets. It now supports PowerPC for the OldWorld emulation. As a result it is now possible to use Debian PowerPC under QEMU emulating an OldWorld machine.

What works?

• Display (partly), keyboard, hard disk, network;
• Booting from CD-ROM or from disk using Quik;
• Installation of Debian Etch or Lenny (but due to a bug in debian-installer quik.conf has to be fixed manually);
• Standard Debian kernels;
• G3 CPU emulation: the testsuite results of the GNU libc 2.7 and of GCC 4.3 (Debian packages) are the same than on a real machine.
• virtio devices

What doesn't work / has to be done?

• A few devices part of the MacIO chipset are not emulated and/or are replaced by other devices: IDE, SCSI, Ethernet and sound;
• The red and green colors are reversed, in some modes only (in debian-installer for example);
• X only outputs some strange images;
• PCI devices using I/O ports don't work (like the RTL8029 card, or the RTL8139 card with the 8139too driver).

For those who want to test, an Etch image is available. You will need to compile QEMU by manually given that the version in Debian is too old and that openbios-ppc is still in the NEW queue.

As already announced by Julien Blache, I successfully passed my PhD defense today, and I am now a doctor.

During my PhD, I designed and implemented an optical simulator for the MUSE instrument, an integral field spectrograph which will be installed on one of the large European telescopes of the VLT.

As I am one of those who have read "able" instead of "unable", I had to find a really cheap flight. This may sound crazy, but an Iberia flight to Buenos Aires from Berlin costs far less than from Lyon (where I live) or even from Madrid: 781.12 EUR from Berlin instead over 1,200.00 EUR from Madrid and over 1,300.00 EUR from Lyon (in both cases with a change in Madrid Barajas).

I wonder if Iberia pays you 420,00 EUR if you flight from Berlin to Madrid...

Now I have to find a cheap way to go to Berlin from Lyon (probably an EasyJet flight). I plan to spend a few days of holiday in Berlin before flying to Argentina.

Dear lazyweb, I encounter MTU problems with an IPsec setup and NAT.

Here is a simplified version of my setup:

remote host < --- internet ---> (eth0) gateway (eth1) < --- LAN

As you may have guess, the gateway has only one public IP address and thus the hosts on the LAN are connected to the internet through NAT.

The connection between the remote host and the gateway is secured using IPsec (kame tools), and this works as expected as long, as the connection is done between the remote host and the gateway. The problems arise when I try to make a connection between the remote host and one host from the LAN. Due to the use of IPsec, the MTU is reduced by 44 bytes, however "ICMP need to frag" packets are not emitted by the gateway, so the connection just hangs.

I have tried various solution from the web (setting MTU on the various interfaces, clamping MSS with iptables, defining advmss with ip route, etc.), and the only one which actually works is reducing the MTU on the LAN hosts. Not very useable given that they are a lot of hosts on the LAN.

Note that when IPsec is disabled, if I lower the MTU of eth0, the "ICMP need to frag" packets are correctly emitted, and the connection just works.

Suggestions?

Some of you may have noticed that I was mostly unavailable those last weeks. I was finishing writing my PhD report. It is now submitted, so I have more free time again.

I am currently processing the backlog. If you are waiting for an action from my side, you should get some news in the next few days.

Today I upgraded my BIOS in the hope to solve various issues. When I rebooted the machine, it didn't get an IP address through DHCP: the Ethernet MAC address has been changed by the BIOS upgrade.

Now compare the old and the new Ethernet MAC addresses:

old address: 0:1a:4d:60:72:e0
new address: e0:72:60:4d:1a:0

Time to laugh...

We now have a second GNU/kFreeBSD build daemon building the kfreebsd-amd64 architecture. It has been kindly offered and is hosted in UK by The Positive Internet Company Ltd.

It adds redundancy to our buildd network, which is important given that the other kfreebsd-amd64 build daemon machine is on a simple ADSL line, and so less reliable than a machine in a datacenter.

For those who want to know more, here is the current status of the GNU/kFreeBSD buildd network:

• callisto.debian.net (kfreebsd-amd64)
  2 x Opteron 1.4GHZ, 1GB RAM
  Hosted by The Positive Internet Company
• shockley.aurel32.net (kfreebsd-amd64)
  Sempron 2600+, 1GB RAM
  Hosted by Aurelien Jarno (ADSL)
• hagrid.debian.net (kfreebsd-i386)
  PIII 800 MHz, 512MB RAM
  Hosted by ETH Zürich
• maxwell.aurel32.net (kfreebsd-i386)
  Sempron 2600+, 1GB RAM
  Hosted by Aurelien Jarno (ADSL)

My goal is to eventually get rid of all build daemons that I am hosting at home on my ADSL line, though that is less critical now.