[et-mgmt-tools] VM images

[David Lutterkort]

On Tue, 2007-06-12 at 08:39 +0100, Mark McLoughlin wrote:
> > It'd probably make more sense if the metadata could express what
> > partitions with what FS's should be on disks - then auto-creation of
> > scratch or user disks could actually be useful for appliance builders.
> 
> 	You're confusing me now - my ImageInstaller had support for formatting
> auto-created disks and I thought you didn't like that idea. My point was
> going to be that auto-creating disks is useless without formatting
> support.
> 
> 	Does that mean we agree now? :-)

Definitely; the only thing that bothered me about the ImageInstaller was
that it didn't export full disks to the VM, only partitions. I think it
would be very useful to expand this code to take FS images and build
disks from them (or create disks with formatted partitions)

> > >    - This looks odd:
> > > 
> > > +    order = [ "xen", "kvm", "kqemu", "qemu" ]
> > > +    for o in order:
> > > +        if types.count(o) > 0:
> > > 
> > >      i.e. it'd be better not to have to keep that list updated. How 
> > >      about you just pick the first type? If libvirt doesn't order the 
> > >      list of available types in a useful order, maybe it should?
> > 
> > Agreed; going just by the order in the metadata seems cleaner. If we do
> > that, then there's no need for libvirt ordering the types.
> 
> 	Huh? You don't have the hypervisor type in the metadata. And rightly
> so.

I'll read my own code at some point ;)

> 	So, I'm suggesting that we go by libvirt's ordering rather than a
> hard-coded ordering.
> 
> > >    - Shouldn't we be copying even system disk images, unless they're 
> > >      read-only, on instantiation - i.e. you should be able to run 
> > >      virt-image multiple times.
> > 
> > I kinda left the issue of multiple instantiations of images out on
> > purpose, to keep the first cut simple, since they require a good deal of
> > book-keeping, too, to make image-based updates possible.
> 
> 	I think it's pretty natural to assume people will run virt-image more
> than once.

Absolutely, I just didn't want to deal with it in the first round.

David