[openstack-dev] [networking-ovn][Neutron] OVN support for routed networks(plugin interface for host mapping)

Russell Bryant rbryant at redhat.com
Thu Mar 17 02:35:13 UTC 2016

On Tue, Mar 15, 2016 at 7:02 PM, Hong Hui Xiao <xiaohhui at cn.ibm.com> wrote:

> Hi all.
> I did some investigation recently. And I think we can start some
> discussion now.
> All below thinking is based on the current implementation of neutron. With
> routed network, a subnet will be considered as a L2 domain. Things might
> change.
> I think routed network in OVN can implement in this way:
> User creates provider network. For example:
> neutron net-create provider-101 --shared \
> --provider:physical_network providernet \
> --provider:network_type vlan \
> --provider:segmentation_id 101
> These attributes "--provider:physical_network" will be recorded in the
> external_ids of Logical_Switch in OVN_Northbound.

> To Russell:
> I will expect OVN to do the following things.
> 1) The OVN_Southbound will have the latest information of
> "ovn-bridge-mappings" of each Chassis.
> 2) After creating a new network with "provider:physical_network" set, the
> OVN will update Logical_Switch in OVN_Northbound.
> The Logical_Switch will have new key:value pair in external_ids.
> neutron:available_hosts="compute-host1,compute-host2"
> 3) When a compute host join/leave the OpenStack topology, or a compute
> host just updates its ovn-bridge-mappings, OVN should updated
> Logical_Switch with related physical_network. This is a bottom-up change,
> which is similar to the port status change.
> 4) networking-ovn should be able to catch the update of Logical_Switch in
> 2) & 3) and update the SegmentHostMapping, which will be introduced in
> [2].
> I think 1) 2) & 3) need additional work in OVN code. And 4) need code
> change in networking-ovn.

​There's some work happening in OVN where the information currently in
ovn-bridge-mappings on each hypervisor will become accessible in the OVN
Southbound database.

As a nice side effect, the Neutron plugin should be able to read those
bridge mappings from the OVN database and have all of the information it

Russell Bryant
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openstack.org/pipermail/openstack-dev/attachments/20160316/ecf861b6/attachment.html>

More information about the OpenStack-dev mailing list