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I'm using cobbler and koan to install virtual guests on a Xen installation. The kickstart file does the install and then reboots. However, the configuration of the guest (from dumpxml in virsh) shows:


instead of "restart" so the machine halts and then I have to start it up manually to continue the configuration. After the restart, the configuration seems to be OK because then the on_reboot option is set to restart.

Does anyone know how to get this to work right?

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It is being done right as it is.

During the installation phase of a Xen virtual machine, the VM is booted in a slightly This is because of the way pygrub (not the actual grub) handles the booting of a virtual machine. We need to use pygrub because of the para-virtualized nature of Xen. Pygrub is used to 'feed' a kernel to the virtual machine.

The VM boots a kernel that is in the host OS the first time, while it is 'inside' the VM afterwards. This calls for reconfiguring the VM a bit after install, so it needs to be shut down, not rebooted. After that, a reboot will be a reboot.

Take a look here real quick, or, for a more elaborate answer, take a look here, near "Lifecycle control".

Maybe someone with a bit more experience with Xen can write a comment here about why, exactly, the 'destroy' is needed the first time.

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I can't find any clear deep explanation on the reasons of the first reboot destroy near "Lifecycle control" neither in the other link you provide. Any link pointing to a more detailed explanation ? Thanks – drAlberT Sep 2 '09 at 8:51
Your answer is in "This allows the VM to be re-configured for the first post-install bootup. " in the "Lifecycle control" section. As I said, the first time a VM boots, it's kernel is in the host OS, afterwards, the kernel is in the VM. That calls for reconfiguring, which calls for a complete powerdown. – wzzrd Sep 2 '09 at 12:00

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