Kernel problems with unionfs and Ubuntu gutsy

[Eymen Alyaz]

R. F. Grant wrote:
> Hi all,
>
> We recently got some new PCs with more recent hardware. The existing FAI
> setup we had no longer worked with the new hardware - presumably because the
> fai kernels we were using (Fai 3.1.8) did not contain the necessary drivers.
>
> I began setting up a new FAI server from scratch on a new PC (so as not to
> break the existing FAI server which still works for all our older PCs).
>
> The fai versions I am using are:
>
> fai-client                            3.2.4
> fai-doc                               3.2.4
> fai-quickstart                        3.2.4
> fai-server                            3.2.4
>
> The PC I am installing the server on is running Ubuntu Feisty:
>
> Linux 2.6.20-16-generic #2 SMP Tue Feb 12 05:41:34 UTC 2008 i686 GNU/Linux
>
> I am trying to install Ubuntu Gutsy onto the client PCs (since the Gutsy
> kernel
> contains the necessary hardware drivers).
>
> Doing a manual install of Gutsy on a new PC works just fine.
>
> The trick, then, seems to be getting a correctly functioning kernel for FAI
> to use. As far as I can tell, the requirements are:
>
> 1) Must be able to run the hardware (so at least 2.6.22)
> 2) Must be patchable so that unionfs will work
>
> After trying many kernels, I also find an extra annoyance. The new PCs
> contain
> Intel Q35 motherboards which contain a known bug: they will not boot from a
> regular kernel unless you add pci=nommconf or acpi=off. There is a patch
> that
> is supposed to fix this for 2.6.24 kernels, although I have not had much
> luck
> with this.
>
> Anyway, I finally managed to build a kernel that would boot the new
> hardware.
> I built it by:
> - installing a new PC with Ubuntu Gutsy by hand
> - downloading the 2.6.24.2 kernel source
> - downloading the correct unionfs patch for this kernel
> (unionfs-2.2.4_for_2.6.24.2.diff.gz) and applying it (no error messages)
> - copying the existing kernel config file from Gutsy's 2.6.22 kernel (and
> running make menuconfig to add unionfs to the kernel) and using
> it to build a new 2.6.24 kernel
>
> Installing this kernel on the new PC, it booted up fine as long as I
> included
> the comment pci=nommconf in the boot parameters.
>
> (I tried the kernel patch to fix the mmconf problem, but that kernel refused
> to boot.)
>
> Anyway, I then installed the newly created 2.6.24.2 kernel in the nfsroot on
> the fai server, and then copied the linux-image and initrd files to
> /srv/tftp/fai. I tweaked the config file in pxelinux.cfg to refer to
> this new
>  kernel.  Then I set fai going. (We run a dhcp server to kickstart FAI with
> a network book. This all seems to work just fine.)
>
> Fai starts up, finds the correct kernel, and begins loading drivers. (If
> I do
> not include the pci=nommconf bit in the pxelinux.cfg file then it just hangs
> almost immediately, but it seems to start working in the usual way if I do
> include it). However, it then crashes out with a kernel panic:
>
> Kernel panic - not syncing: Attempted to kill init!
>
> This occurs just after loading drivers for USB, Sata drives and the CD
> drive.
>
> I have also tried building a kernel from the Ubuntu gutsy archive
> (2.6.22-14.52)and managed to apply the unionfs patch (albeit with some
> error messages). This
> will also boot the new hardware (with the pci=nommconf option) but
> crashes in
> the same way when booting with FAI. Interestingly, this kernel will
> *occasionally* boot an older pc into FAI, but more often than not it
> hangs just
> before loading the unionfs stuff. (I have been unable to reproduce building
> this kernel as well - it always crashes out during the build of the unionfs
> stuff, so I'm not sure what magic I used the first time round.)
>
> So, the questions:
> - If a kernel will boot the PC in normal circumstances,
> is it unreasonable to assume that it should also just work as the fai
> kernel?
> (assuming unionfs is correctly working, of course...)
> - Is adding a boot tag pci=nommconf in the fai pxelinux.cfg file likely
> to causeproblems?
> - Are there any known problem in trying to use FAI to install ubuntu gutsy
> (from a feisty server)
> - Does anyone have any idea how to resolve this problem?
>
> I can, of course, provide any other information required. Fai does not get
> far enough to start producing logs, though...
>
> Sorry for the long post - just trying to explain what has been a long and
> frustrating process thus far...
>   

Hello

I'm also setting up FAI to install new Ubuntu distributions.
Currently I'm working on Hardy Heron.
The ubuntu kernels (gutsy, hardy) have problems mounting unionfs over
FAI nfsroot.
Therefore I use plain Debian Etch kernel on my TFTP server to boot my
install clients.
I also build my nfsroot from Debian Etch bootstrap.
On the install clients I do install ubuntu kernels which work as expected.


Regards,
Eymen Alyaz