Re: how to multiboot xen with grub2 on Ubuntu

[Abhishek Dixit]

On Wed, Mar 9, 2011 at 2:54 AM, Abhishek Dixit <address@hidden> wrote:
> On Wed, Mar 9, 2011 at 2:53 AM, Abhishek Dixit <address@hidden> wrote:
>> On Wed, Mar 9, 2011 at 2:47 AM, Jordan Uggla <address@hidden> wrote:
>>>> menuentry "Xen Linux 2.6.32.27" {
>>>>       insmod ntfs
>>>>       set root='(hd0,2)'
>>>>       loopback loop0 /ubuntu/disks/root.disk
>>>>       set root=(loop0)
>>>>       kernel (hd0,2)/boot/xen.gz
>>>>       module (hd0,2)/boot/vmlinuz-2.6.32.27 dummy=dummy
>>>> root=/dev/sda2 loop=/ubuntu/disks/root.disk ro console=tty0
>>>>       module (hd0,2)/boot/initrd.img-2.6.32.27
>>>> }
>>>>
>>>>
>>>> Entry 2 which failed is
>>>>
>>>> menuentry "Xen Linux 2.6.32.27" {
>>>>        insmod multiboot2
>>>>        set root='(hd0,2)'
>>>>        set root=(loop0)
>>>>        kernel (hd0,2)/boot/xen.gz dummy=dummy
>>>>        module (hd0,2)/boot/vmlinuz-2.6.32.27 dummy=dummy
>>>> root=/dev/sda2 loop=/ubuntu/disks/root.disk ro console=tty0
>>>>        module (hd0,2)/boot/initrd.img-2.6.32.27
>>>> }
>>>
>>> Compare these with the entry given in the instructions that you linked to:
>>>
>>> menuentry "Xen 4 / Ubuntu 10.04 kernel 2.6.32.12" {
>>>  insmod ext2
>>>  set root='(hd1,5)'
>>>  multiboot (hd1,5)/boot/xen.gz dummy=dummy dom0_mem=1024M
>>>  module (hd1,5)/boot/vmlinuz-2.6.32.12 dummy=dummy nopat
>>> root=/dev/sdb5 ro console=tty0
>>>  module (hd1,5)/boot/initrd.img-2.6.32.12
>>> }
>>>
>>> Notice there is no "kernel" command in grub2, you need to use "multiboot".
>> Ok
>>> Also, since I assume your /boot/ is within your wubi root.disk rather
>>> than in "(hd1,5)" you should remove (hd1,5) from your file paths to
>>> end up with an entry like:
>>>
>>> menuentry "Xen Linux 2.6.32.27" {
>>>        insmod ntfs
>>>        set root='(hd0,2)'
>>>        loopback loop0 /ubuntu/disks/root.disk
>>>        set root=(loop0)
>>>        multiboot /boot/xen.gz
>>>        module    /boot/vmlinuz-2.6.32.27 dummy=dummy root=/dev/sda2
>>> loop=/ubuntu/disks/root.disk ro console=tty0
>>>        module    /boot/initrd.img-2.6.32.27
>>> }
>>>
>>> --
>> I tried exactly the above entries which you mentioned on grub prompt
>>
>> grub>        insmod ntfs
>> grub>        set root='(hd0,2)'
>> grub>        loopback loop0 /ubuntu/disks/root.disk
>> grub>        set root=(loop0)
>> Upto here things worked perfectly
>> but the moment I did
>> grub>        multiboot /boot/xen.gz
>>
>> I got error
>> error: file not found.
>> Here what am I missing?
> Sorry I mistyped the error
> the error was
> error: unknown command 'multiboot'
>
> and when I do
> grub> insmod multiboot
> error:file not found.
>
 It looks like this grub setup has just enough modules to use loopback
 file on ntfs, but the ACTUAL /boot directory is on the loopback NOT
 ntfs (hd0,2). Therefore any attempt to read any files from (hd0,2)
simply wont work, cause there's no file there.How can I trouble shoot
this
troubleshoot ntfs-loop-xen combination.