On Fri, Feb 26, 2010 at 07:47:20PM +0100, Daniel Dehennin wrote: The goal of the libvirt XML format is to provide a representation that is consistent across all hypervisors, so that regardless of whether using Xen, KVM, or VMWare an config parameter can be encoded that same way. If we were to support your suggestion, every hypervisor in libvirt would end up with a different XML configuration. In addition KVM / QEMU have a history of renaming/breaking command line options, so there's no way of guarenteeing that '-foo' from QEMU 0.9.1 still works with QEMU 0.10.0 or vica-verca. If you have specific KVM arguments that libvirt does not yet support then please either file a RFE bug report with details, or raise the issue on this mailing list WRT your example of -startdate, I posted patches for supporting that last week http://www.redhat.com/archives/libvir-list/2010-February/msg00104.html Regards, Daniel -- |: Red Hat, Engineering, London -o- http://people.redhat.com/berrange/ :| |: http://libvirt.org -o- http://virt-manager.org -o- http://deltacloud.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: GnuPG: 7D3B9505 -o- F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 :|