Kernel problems with unionfs and Ubuntu gutsy

[Sjors Robroek]

Eymen Alyaz wrote:
> 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.
>   

Yes, i've encountered the same problem as well. You need to use either a 
debian or ubuntu dapper kernel/initrd for both your bootstrap and nfsroot.

I've made a few bug requests on launchpad but nothing's happened with it 
for over 6 months now.
>
> Regards,
> Eymen Alyaz
>