On 12/13/06, Jane Dogalt <jdogalt(a)yahoo.com> wrote:
In my project, I'm using qemu to generate system images as a
user. I've never used xen, as I have yet to discover as trivial a
usage of it as qemu provides. (i.e. no configuration, a simple
commandline, and there you are booting a livecd in a window).
I'm wondering if any of you, particularly xen leaning redhat
have considered using it as a sandbox to create installed system images
in? E.g. that could then be modified by a script, and rolled into a
For doing generic installs, the combination of qemu, kqemu and vde2
would be difficult to beat. In addition to running in user space, as
you pointed out, qemu provides a pure emulation model for a target
processor, bios, network device and video card. The optional kernel
acceleration module raises it's performance to nearly bare metal.
Xen has a different architecture... it's a true hypervisor that
requires a kernel presence and either cpu support for pure
virtualization (vmx:Intel, smx:AMD) or modifications to the guest os.
As a result, it's not very useful for doing arbitrary os image builds
from generic install media. FC6 provides a Xen aware kernel that can
be used with the Virtual Machine Manager to do kickstart vm image
builds. Patched dom0 and guest os kernels are also available from
along with a live cd demo.
I'm planning to do a lot more work with Xen. It's fast, efficient and
ideal for consolidating groups of underutilized servers into a few
well provisioned machines. For building portable install images from
generic media, however, qemu will remain my tool of choice.