How to instruct XenServer's host virtual machine to boot from ISO CD/DVD image

Objective

Here we assume that you have already created VM's device to link to desired ISO image you wish to boot from. The objective is to instruct XenServer's host virtual machine to boot from ISO CD/DVD image instead of default VDI disk. Failure to do so may result in following error message:

The bootloader returned an error
msg: Unable to find partition containing kernel

Requirements

Administrative Local or Remote command line access to XenServer is required to complete this task.

Instructions

Obtain VM UUID

Obtain UUID of the virtual machine you would like to boot from the ISO CD/DVD image. For example:

# xe vm-list
uuid ( RO)           : c2e2329c-6637-6db5-eb04-a59d16487e10
     name-label ( RW): openSUSE42
    power-state ( RO): halted


uuid ( RO)           : 87814cf9-22d4-4bc4-afaa-ae95a3b10aff
     name-label ( RW): Control domain on host: xenserver
    power-state ( RO): running


uuid ( RO)           : 9db43f69-28e7-53f8-fa33-bf4d100b891a
     name-label ( RW): Debian8
    power-state ( RO): running

Set new boot policy

Using the VM UUID set a new boot policy to "Bios order". Example:

# xe vm-param-set HVM-boot-policy="BIOS order" uuid=c2e2329c-6637-6db5-eb04-a59d16487e10

Disable ISO boot

Once you performed operating system installation you may need to disable ISO boot:

# xe vm-param-set HVM-boot-policy="" uuid=c2e2329c-6637-6db5-eb04-a59d16487e10