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On Thu, May 21, 2015 at 09:34:20PM +1200, Xav Paice wrote:
> On 21/05/15 21:23, Daniel P. Berrange wrote:
> > On Wed, May 20, 2015 at 03:01:50PM -0700, Michael Still wrote:
> >> I note that we use instance.name to lookup the libvirt domain a bunch
> >> in the driver. I'm wondering why we don't just use instance.uuid all
> >> the time -- the code for that already exists. Is there a good reason
> >> to not move to always using the uuid?
> >>
> >> I ask because instance.name is not guaranteed to be unique depending
> >> on how weird the nova deployment is.
> > Agreed, there's no benefit to using name - internally libvirt will always
> > prefer to use the UUID itself too.
> >
> > These days though, there is only a single place in nova libvirt driver
> > that needs updating - the nova.virt.libvirt.host.Host class get_domain()
> > method just needs to be switched to use uuid.
> 
> Just a comment from an ops point of view - it would be miles easier when
> trying to troubleshoot, if the instance name was the uuid anyway.  I
> totally agree on using instance.uuid, just to comment that I find it a
> little painful sometimes that instance names don't match the uuid of the
> instance, but the directory structure does.  Just a bit of confusion to
> avoid at 2am when something isn't working.

You do know you can configure the instance name used...

eg in nova.conf

  instance_name_template='inst-%(uuid)s'

Regards,
Daniel
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