Open Stack

On Thu, 2012-11-01 at 16:34 -0400, Russell Bryant wrote:
> On 11/01/2012 12:12 PM, Mark McLoughlin wrote:
> > Hey,
> > 
> > For the first time (that I'm aware of) we have a request to include a
> > backport on the stable branch which includes a change to the RPC API:
> > 
> >   https://review.openstack.org/14754
> > 
> > This is troublesome for a couple of reasons:
> > 
> >   1) People upgrading to a version which includes this change would 
> >      need to be aware that they should update their compute services
> >      before updating their API services
> > 
> >   2) While in this case we're backporting the first RPC API change 
> >      since Folsom (i.e. version 2.2 was in Folsom, this is version 2.3)
> >      if we were backporting a later API version we would have to give 
> >      up on retaining Folsom compatibility in Grizzly
> > 
> > In this particular case, I'm somewhat hopeful we might be able to figure
> > out a fix which doesn't involve the API change but that remains to be
> > seen.
> > 
> > Any ideas?
> 
> It looks like Vish took care of it.  The new version maintains rpc API
> backwards compat.
> 
> https://review.openstack.org/#/c/14754/2/nova/compute/manager.py

Any RPC API changes (even backwards compatible) are a problem on the
stable branch - users need to know to upgrade in a certain order and we
also have the issue with linear versioning issue on two branches

Cheers,
Mark.