Open Stack

> For those deprecated options, does it mean it won’t be supported in 
> Mitaka and future release at all? Or is there a grace period so that 
> we, as a user, can gradually transition from Liberty to Mitaka?

The deprecation period is usually one cycle for something like this.
That means people get a chance to clean up their configs before we
remove it which would cause an error if it's still in there.

> What is the rationale of some deprecated options, for example, 
> “[DEFAULT]network_api_class”. It seems to me that it provides end 
> users with flexibility in configuring backends.

The rationale is that this is not a plugin interface. It's not stable in
any way and not something we want to be randomly plug-able by people.
The reason it's in there now is historical. We have removed almost all
of the other plug points that work like this, and had neglected to
remove this one because it is used internally by our
nova-network/neutron switching. However, it need not be exposed for
that, and the need for it even internally will be going away soon anyway.

> So what is the rationale of deprecating this option and is there
> equivalent method in Mitika to replace this option?

There is not, and there are no plans to add one since we want to remove
the plug-ability entirely.

--Dan