Cannot install ubuntu or other linux flavours on citrix Xen server

Citrix Xen sucks!

When u try to install linux stuff on its Xen servers, u will get an error complaining errors like below:

'

......the bootloader for this VM returned an error -- did the VM installation succeed? INVALID_SOURCE Unable to access a required file in the specified repository: file:///tmp/cdrom-repo-GlSDP2/install/vmlinuz.

'

This is a bug of xen and the real cause is the missing boot order config for the new vm instance.

We can fix it this way(http://discussions.citrix.com/topic/237726-unable-to-install-linux-guest/):

root@xcpBlade1 ~# xe vm-param-list uuid=92497771-078b-8977-4ec0-0243515d924d| grep HVM-boot 
HVM-boot-policy ( RW): 
HVM-boot-params (MRW):

root@xcpBlade1 ~# xe vm-param-set uuid=92497771-078b-8977-4ec0-0243515d924d HVM-boot-policy=BIOS\ order HVM-boot-params:order="dc"

root@xcpBlade1 ~# xe vm-param-list uuid=92497771-078b-8977-4ec0-0243515d924d| grep HVM-boot 
HVM-boot-policy ( RW): BIOS order 
HVM-boot-params (MRW): order: dc

and bang! problem solved