Re: [libvirt] libguestfs integration: rich disk access for libvirt applications

On Wed, Sep 28, 2011 at 11:14:57AM +0100, Stefan Hajnoczi wrote: > On Tue, Sep 27, 2011 at 12:55 PM, Richard W.M. Jones <rjones(a)redhat.com&gt; wrote: > > To put this all into one place: > > > > (1) An ugly new libvirt API that runs febootstrap-supermin-helper to > > create the appliance. > [...] > > I'm worried about item (1) in this list ... > > This is the only instance where libvirt knows about libguestfs. All > other steps are libguest only or involve libguestfs knowing about > libvirt. > > Would it be possible introduce a "domain-builder" concept into > libvirt? When libguestfs is installed it drops a domain-builder > configuration/script that libvirt can pick up. Then you can say > something like virDomainBuild(name="guestfs-appliance", > builder="guestfs"). We do have a historical syntax from Xen paravirt which lets us call out to a helper at boot time, namely the "<bootloader>" element. With Xen this is typically something like pygrub, or pxegrub, which does some work and writes out a kernel+initrd into temporary files, and prints the file paths + any kernel args on stdout. We could just wire up this concept in KVM too without any real trouble, and then we could have guestfs-bootloader script todo the magic setup