[libvirt] fully virtualized xen guest question

[Daniel P. Berrange]

On Thu, Jul 31, 2008 at 11:31:39PM +0200, Christoph H?ger wrote:
> I am running XEN on an debian etch. For clustering purposes I wanted to
> boot fedora as virtual machine. 
> 
> That works (except for nfs mounts) fine using the paravortualization
> features.
> 
> But fully virtulalized guests do not even boot, I do not get any
> sensefull error message, my config file looks like:
> 
> <domain type='xen'>
> <name>werewolf</name>
> 
> <os>
>         <type>hvm</type>
>         <loader>/usr/lib/xen-3.0.3-1/boot/hvmloader</loader>
> 
> <kernel>/data/virtual/kernel/kvm1/vmlinuz-2.6.18-6-amd64</kernel>
> 
> <initrd>/data/virtual/kernel/kvm1/initrd.img-2.6.18-6-amd64</initrd>
>         <cmdline>root=/dev/hda1</cmdline>

Booting fullyvirtualized guests off a kernel+initrd is a very new
feature in Xen. Your <loader> path suggests you are using Xen 3.0.3
which is no where near new enough to support this. You need to boot
of CDROM or hardisk instead.

> <domain type='xen'>
> <name>werewolf</name>
> 
> <os>
>         <type>hvm</type>
>         <loader>/usr/lib/xen-3.0.3-1/boot/hvmloader</loader>
> 
> <kernel>/data/virtual/kernel/kvm1/vmlinuz-2.6.18-6-amd64</kernel>
> 
> <initrd>/data/virtual/kernel/kvm1/initrd.img-2.6.18-6-amd64</initrd>
>         <cmdline>root=/dev/hda1</cmdline>
> </os>
>   <memory>524M</memory>
>   <vcpu>1</vcpu>
>   <devices>
>         <emulator>/usr/bin/kvm</emulator>

Urm, you're trying to use KVM with Xen which just won't work. You
need to point to Xen's version of QEMU /usr/lib/xen/bin/qemu-dm
or whereever Debian puts it.

> all I get when tryin virsh create is:
> 
> xend_post: error from xen daemon: (xend.err "Error creating domain: (0,
> 'Error')")

This looks like a fairly old Xen which didn't know how to give proper
error messages. You'll have to check /var/log/xen/ for more details,
but it'll certainly be the kernel/initrd stuff that's broken, and the
device emulator too.

Daniel
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