Open Stack

My original thinking (given that others would agree that separate plugin(s) for L3/routing is a good idea, and it seems people do) was to start modestly by simply refactoring the mixin to become a plugin, adhering to the SI framework being developed. Getting that into Grizzly would be a good baseline. I think this is also what you were proposing in your "9 november 2012 13:56" email? I'm willing to do work on this, or actually I am doing work on it already that hopefully can be of use. I understand you're going to migrate the L3 API to core and these two efforts clearly have connections.

About your comment/question about further decomposing the different L3 routing functionality into separate L3 plugins, my spontaneous proposal is to keep it as one plugin for now. Then as discussions and work evolve on the L3 APIs, VPNs, NAT etc we can revisit this and make further splits if that turns out to make sense.

/ Bob



From: Salvatore Orlando <sorlando at nicira.com<mailto:sorlando at nicira.com>>
Reply-To: OpenStack Development Mailing List <openstack-dev at lists.openstack.org<mailto:openstack-dev at lists.openstack.org>>
Date: fredag 9 november 2012 15:35
To: OpenStack Development Mailing List <openstack-dev at lists.openstack.org<mailto:openstack-dev at lists.openstack.org>>
Subject: Re: [openstack-dev] Quantum L3 router, mixin or plugin?

I did not notice Bob already filed a blueprint.
This is good for me as it saves me some time :)

Do you have already a plan for delivering this work item? Let me know if I can help in any way.

Salvatore

On 9 November 2012 15:26, Salvatore Orlando <sorlando at nicira.com<mailto:sorlando at nicira.com>> wrote:
Replies inline.

On 9 November 2012 15:03, Ian Wells <ijw.ubuntu at cack.org.uk<mailto:ijw.ubuntu at cack.org.uk>> wrote:
On 9 November 2012 12:42, Bob Melander (bmelande) <bmelande at cisco.com<mailto:bmelande at cisco.com>> wrote:
Ok, I'm willing to work on this and I've created a blueprint to kick it off (https://blueprints.launchpad.net/quantum/+spec/quantum-l3-routing-plugin)

I too think VRRP (and some other features) would be nice to add. However, the first steps would be to take the inherited mixin and transform that into a plugin. That ought to be possible with fairly limited effort. Though there are some dependencies that need to be sorted out. In particular, core plugin methods like  create_network(…)make calls to mixin functions such as _process_l3_create(…), _extend_network_dict_l3(…), _process_l3_update(…):


self._process_l3_create(context, network['network'], net['id'])

…

self._extend_network_dict_l3(context, net)

One point here is that I would like to be able to create an unrouted network.  Creating a network *with* a router is a composite call (and in any case, shouldn't I be able to create a network and add a router later on?) and I don't think that functionality should be baked into create_network if we can avoid it.

That how we do it, actually.

1) POST /networks
Create a l2 network
2) POST /subnets with reference in body to previously created network
Defines a IP address range on the L2 network
3) POST /routers
Defined a l3 forwarding element
4) PUT /routers/<router-id>/add-router-interface
Connects a subnet to a router


I'm aware this breaks backward compatibility in the way I've described it, but just my 2c.  (Perhaps create_network becomes a thin wrapper over a more fundamental call, create_bare_network?)

The methods pointed out by Bob are not really for creating a router with a network; they are for managing the additions that the l3 API extensions makes to the "network" resource in order to handle "external" networks properly. I have more on then in my previous post.


There's reasons why you might want that: in a layered application, HA -> cache -> web appservers  -> DB for instance, most of the inner networks you might create for such a topology have no need of external routeability.  At the moment the rule seems to be 'if you don't need it, don't use it' but it would be nice to simply not have the router there in the first place.

Totally agree. Quantum v1 actually did not have any router and built multi-tier topologies as you describe them. The router is not necessary, and if you don't need it it does not get created.



--
Ian.


_______________________________________________
OpenStack-dev mailing list
OpenStack-dev at lists.openstack.org<mailto:OpenStack-dev at lists.openstack.org>
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/20121112/501cac78/attachment.html>