Support OVN native L3 routing

[Han Zhou]

Distributed L3 routing is supported in OVN but not yet in networking-ovn plugin. The existing code for router interface adding/deletion are outdated and not working with latest OVN NB schema.

To support OVN's L3 (no gateway), we need to create logical router port on lrouter and its patch port on connected lswitch when router interface is being added.

With this support, ports on different subnets will be able to talk to each other by connecting the subnets to same router.

[Amitabha Biswas (azbiswas)]

Part of the solution is being worked on by https://review.openstack.org/#/c/237820/

[yong sheng gong (gongysh)]

Isn't the router DVR by default? can u create non-dvr router in ovn plugin?

[Han Zhou (zhouhan)]

@Yongsheng, yes, it is DVR only. The work mentioned by @Amitabha satisfies the requirement. I didn't notice that review until posting this bug. In fact I was working on a redundant code: https://review.openstack.org/#/c/243385/ which worked for my testing purpose.

[Russell Bryant (russellb)]

We should probably avoid using the term "DVR" for OVN's L3 support since DVR means something very specific in Neutron. OVN's routing is indeed distributed, but shares no code with Neutron's DVR and is implemented in a *very* different way.

[Han Zhou (zhouhan)]

Russell, thanks for clarifying.

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/237820
Committed: https://git.openstack.org/cgit/openstack/networking-ovn/commit/?id=35746b418926b38428e573fdaf38bab4acb0c926
Submitter: Jenkins
Branch: master

commit 35746b418926b38428e573fdaf38bab4acb0c926
Author: Chandra S Vejendla <email address hidden>
Date: Wed Oct 14 11:32:11 2015 -0700

    Add/delete router interfaces

    This patch set adds support for add/delete router interfaces.
    Adding router port involves:
        - Create row in logical_router_port table
        - Update the ports in logical_router table with the
        logical_router_port added above
        - Update the options column in logical_port table with
        {router-port: "UUID of logical_router_port"}
        - set the type column in the logical_port table to "router"

    Deleting router ports:
        - Look for port_id if port_id not present in incoming request
        - Delete the router port from the logical_router table
        The logical_router_port entry will be garbage collected

    Added a config variable OVN_L3_MODE which when set to false,
    will default to using q-l3 instead of OVN L3. This is a temporary fix
    until we resolve OVN l3 issues.

    Closes-Bug: #1514649
    Change-Id: I6fd9ac4ab04be14796422087d3ff716cd4d81e55
    Co-Authored-By: Gal Sagie <email address hidden>
    Co-Authored-By: Amitabha Biswas <email address hidden>

[OpenStack Infra (hudson-openstack)]

Change abandoned by Han Zhou (<email address hidden>) on branch: master
Review: https://review.openstack.org/243385