From Vern Burke:
From my blog post at http://vburke.wordpress.com/2010/01/28/upgrading-xen-cloud-platform-bugs-and-fixes/ and a post to the list about the same date:
In virgin XCP 0.1.1 (right from the install iso), a working CentOS/RHEL 5.4 VM cannot be created, despite there being a template for it. The VM can be created without error but attempting to start it results in a “no output from bootloader†messageâ€
The cause of this is a missing file in the 0.1.1 distribution. Download this file:
http://www.xen.org/files/XenCloud/Software/latest/el5.4-initrd-additions.cpio
Once downloaded, copy it to the /opt/xensource/packages/files/guest-installer directory on your XCP 0.1.1 host, reboot the host, and you’re off and running.