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On 1/29/2014 10:47 AM, Russell Bryant wrote:
> Greetings,
>
> A while back I mentioned that we would revisit the potential deprecation
> of nova-network in Icehouse after the icehouse-2 milestone.  The time
> has come.  :-)
>
> First, let me recap my high level view of the blockers to deprecating
> nova-network in favor of Neutron:
>
>    - Feature parity
>      - The biggest gap here has been nova-network's multi-host mode.
>        Neutron needs some sort of HA for l3 agents, as well as the
>        ability to run in a mode that enables a single tenant's traffic
>        to be actively handled by multiple nodes.
>
>    - Testing / Quality parity
>      - Neutron needs to reach testing and quality parity in CI.  This
>        includes running the full tempest suite, for example.  For all
>        tests run against nova with nova-network that are applicable, they
>        need to be run against Neutron, as well.  All of these jobs should
>        have comparable or better reliability than the ones with
>        nova-network.
>
>    - Production-ready open source components
>      - nova-network provides basic, but usable in production networking
>        based purely on open source components.  Neutron must have
>        production-ready options based purely on open source components,
>        as well, that provides comparable or better performance and
>        reliability.
>
> First, I would like to say thank you to those in the Neutron team that
> have worked hard to make progress in various areas.  While there has
> been good progress, we're not quite there on achieving these items.  As
> a result, nova-network will *not* be marked deprecated in Icehouse.  We
> will revisit this question again in a future release.  I'll leave it to
> the Neutron team to comment further on the likelihood of meeting these
> goals in the Juno development cycle.
>
> Regarding nova-network, I would like to make some changes.  We froze
> development on nova-network in advance of its deprecation.
> Unfortunately, this process has taken longer than anyone thought or
> hoped.  This has had some negative consequences on the nova-network code
> (such as [1]).
>
> Effective immediately, I would like to unfreeze nova-network
> development.  What this really means:
>
>    - We will no longer skip nova-network when making general
>      architectural improvements to the rest of the code.  An example
>      of playing catch-up in nova-network is [2].
>
>    - We will accept new features, evaluated on a case by case basis,
>      just like any other Nova feature.  However, we are explicitly
>      *not* interested in features that widen the parity gaps between
>      nova-network and Neutron.
>
>    - While we will accept incremental features to nova-network, we
>      are *not* interested in increasing the scope of nova-network
>      to include support of any SDN controller.  We leave that as
>      something exclusive to Neutron.
>
> I firmly believe that Neutron is the future of networking for OpenStack.
>   We just need to loosen up nova-network to move it along to ease some
> pressure and solve some problems as we continue down this transition.
>
> Thanks,
>
> [1]
> http://lists.openstack.org/pipermail/openstack-dev/2014-January/024052.html
> [2] https://blueprints.launchpad.net/nova/+spec/nova-network-objects
>

Timely thread.  I was just going through nova/neutron-related blueprints 
and patches yesterday for Icehouse and noted these as something I think 
we definitely need as pre-reqs before going all-in with neutron:

https://blueprints.launchpad.net/neutron/+spec/instance-nw-info-api
https://bugs.launchpad.net/nova/+bug/1255594
https://bugs.launchpad.net/nova/+bug/1258620

There are patches up for the two bugs, but they need some work.

-- 

Thanks,

Matt Riedemann