[Pkg-xen-devel] Bug#657014: Bug#657014: Bug#657014: Wheezy, Squeeze and Ubuntu server 11.10 has missing boot option to Xen

[Pasi Kärkkäinen]

On Mon, Jan 23, 2012 at 06:26:29PM +0100, Erik Hjelmås wrote:
>>> When installing xen-linux-system on a new Dell R810 server, Wheezy,
>>> Squeeze and Ubuntu server 11.10 all boot fine when booted directly into
>>> the standard kernel, but when booting through Xen (after installing the
>>> package xen-linux-system) the boot process hangs as soon as Xen passes
>>> control to the Dom0 kernel:
>>>
>>> "Gave up waiting for root device" etc
>>>
>>> and it gives me Busybox, but it is also frozen, so there's no other
>>> option that reboot.
>>
>> This might be the same issue as #649923. But please could you provide
>> full console logs so we can verify. If you are able to try the patch in
>> that bug or perhaps a backported 4.1 hypervisor that would also be
>> potentially interesting.
>
> its the same behaviour on both squeeze (4.0) and wheezy (4.1)
>
> since everything freezes on boot, I dont have any logs other than the  
> attached screenshot at the time it freezes (or is something logged this  
> early in the boot process by Xen? I can reboot without Xen and inspect  
> other logs)
>

Please set up a serial console so you can capture the full boot messages
from both Xen hypervisor and dom0 kernel.

In your case you can also use the SOL (Serial Over LAN),
provided by the iDRAC management processor.

http://wiki.xen.org/xenwiki/XenSerialConsole


>>> After several days of troubleshooting it turns out that adding dom0_mem
>>> option (e.g. dom0_mem=8192M) to the multiboot line of
>>> /etc/grub.d/20_linux_xen FIXES THE PROBLEM !
>>>
>>> maybe this has to be fixed in the package?
>>
>> That file is provided by grub, not the hypervisor but I don't think that
>> fix will work since a) really it is a workaround not a fix and b) it is
>> not really possible to determine what is the right number to use for any
>> given system.
>
> I agree, my solution is a workaround and not at fix
>
> I first suspected that there was a problem with the initramfs so I added  
> the megasas driver to /etc/initramfs/modules and updated initramfs. This  
> resulted in a "Cannot allocate memory" error (when trying to load the  
> megasas driver) at the same stage in the boot process. And since Busybox  
> is not able to run either, Xen seems to not give any memory available to  
> the Dom0 kernel when it passes control to it in the boot process.  
> Meaning the Dom0 kernel fails immediately since I guess accessing the  
> root devices is one of the first things it tries to do.
>
> I will attempt install squeeze and wheezy on a different older server  
> (Dell R900), during the next couple of days to see of the same error  
> pops up, and Ill look for more log data then ,
>

I assume you have already installed all the latest BIOS/firmware updates etc?

-- Pasi