[openstack-dev] [all] devstack changing to neutron by default RSN

Armando M. armamig at gmail.com
Fri Aug 5 01:15:06 UTC 2016


On 4 August 2016 at 11:35, Sean Dague <sean at dague.net> wrote:

> One of the cycle goals in newton was to get devstack over to neutron by
> default. Neutron is used by 90+% of our users, and nova network is
> deprecated, and is not long for this world.
>
> Because devstack is used by developers as well as by out test
> infrastructure, the major stumbling block was coming up with a good
> working default on a machine with only 1 interface, that doesn't leave
> that interface in a totally broken state if you reboot the box (noting
> that ovs changes are persistent by default, but brctl ones are not).
>
> We think we've come up with a model that works. It's here -
> https://review.openstack.org/#/c/350750/. And while it's surprisingly
> short, it took a lot of thinking this one through to get there.
>
> The crux of it is that we trust the value of PUBLIC_INTERFACE in a new
> way on the neutron side. It is now unset by default (logic was changed
> in n-net to keep things right there), and if set, then we assume you
> really want neutron to manage this physical interface.
>
> If not, that's cool. We're automatically creating a bridge interface
> (with no physical interfaces in it) and managing that. For single node
> testing this works fine. It passes all the tempest tests[1]. The only
> thing that's really weird in this setup is that because there is no
> physical interface in that bridge, there is no path to the outside world
> from guests. That means no package updates on them.
>
> We address that with an iptables masq rule. It's a little cheaty pants,
> however of the options we've got, it didn't seem so bad. (Note: if you
> have a better option and are willing to get knee deep in solving it,
> please do so. More contributors the better.)
>
> It's going to take a bit for docs to all roll over here, but I think we
> actually want this out sooner rather than later to find any other edge
> cases that it introduces. There will be some bumpiness here. However,
> being able to bring up a full neutron with only the 4 passwords
> specified in config is quite nice.
>
> 1. actually 5 tests fail for unrelated reasons, which is that tempest
> isn't probably excluding tests for services that aren't running because
> it makes some assumptions on the gate config. That will be fixed soon.
>
>         -Sean
>
>
So glad we are finally within the grasp of this!

I posted [1], just to err on the side of caution and get the opportunity to
see how other gate jobs for Neutron might be affected by this change.

Are there any devstack-gate changes lined up too that we should be aware of?

Cheers,
Armando

[1] https://review.openstack.org/#/c/351450/


> --
> Sean Dague
> http://dague.net
>
>
> __________________________________________________________________________
> OpenStack Development Mailing List (not for usage questions)
> Unsubscribe: OpenStack-dev-request at lists.openstack.org?subject:unsubscribe
> http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openstack.org/pipermail/openstack-dev/attachments/20160804/59c7f253/attachment.html>


More information about the OpenStack-dev mailing list