"Daniel P. Berrange" <berrange@redhat.com> wrote on 05/12/2010 10:09:41 AM:

> >
> > I wouldn't make it QEMU specific. It should probably go into libvirt.conf,
> > but
> > then libvirt.conf would need to be modified on every machine when
> > installed.
> > How should the code react if no valid UUID is found in the config file?
> > Create a temporary one that changes with every restart of libvirt? Also
> > dmidecode
> > should probably be used on those machine where it returns a valid UUID.
>
> How do we decide that dmidecode is showing a valid UUID though. Is a
> UUID of all 0's, all 1's or all F's valid ?

With high probability, 32 hex chars that are the same can probably be considered 'wrong'.

Some details on how one could handle the different cases of valid/invalid UUIDs:

   libvirtd.conf                dmidecode                handling

        valid UUID          valid UUID      libvirtd.conf UUID overrides dmidecode's UUID
        invalid UUID        invalid UUID      generate a temporary one; new one after libvirtd restart
        valid UUID      invalid UUID      use valid UUID
      invalid UUID        valid UUID      use valid UUID

  Stefan