openstack/neutron
Code Issues Proposed changes

Merge "[OVN] Add documentation/reno for the OVN external port N/S routing"

Browse Source
This commit is contained in:
Zuul
2025-12-03 18:53:02 +00:00
committed by Gerrit Code Review
parent dd4f9884c6 75c8ff55ad
commit c5ccd70f30
2 changed files with 29 additions and 8 deletions
Download Patch File Download Diff File Expand all files Collapse all files

30
doc/source/admin/ovn/sriov.rst
View File

@@ -33,13 +33,27 @@ The only differences required for an OVN deployment are:
or networker nodes)
Known limitations
~~~~~~~~~~~~~~~~~
North/South routing
~~~~~~~~~~~~~~~~~~~
The current SR-IOV implementation for the OVN Neutron driver has a few
known limitations that should be addressed in the future:
A network with an external port (SR-IOV, baremetal), will create a
``HA_Chassis_Group`` register to schedule these external ports in gateway
chassis. The routers (still) use a set of ``Gateway_Chassis`` registers to
execute the scheduling of the gateway port. Now, since the implementation of
[1]_, when a network is connected as an internal network, the Neutron API will
sync the network ``HA_Chassis_Group`` with the gateway port ``Gateway_Chassis``
set. That will make both scheduling methods to be in sync and will collocate
the gateway router port and the external port in the same OVN gateway chassis;
that allows OVN to route the traffic from the external port through the gateway
port.
#. Routing on VLAN tenant network will not work with SR-IOV. This
is because the external ports are not being co-located with
the logical router's gateway ports, for more information take a look at
`bug #1875852 <https://bugs.launchpad.net/neutron/+bug/1875852>`_.
When the network ``HA_Chassis_Group`` is updated, it could be possible that
the currently assigned gateway chassis changes. However, before connecting the
network to the router, this port is used only for DHCP and metadata; the
external port binding change won't interrupt the traffic.
References
~~~~~~~~~~
.. [1] https://review.opendev.org/q/topic:%22bug/2125553%22

7
releasenotes/notes/ovn-external-ports-n-s-routing-89d9761b8d2c3631.yaml Normal file
View File

@@ -0,0 +1,7 @@
---
features:
- |
ML2/OVN now supports North/South routing for external (SR-IOV, baremetal)
ports. Once the internal network is connected to the router, the OVN
external port scheduler is synced with the gateway port one, collocating
the external and the gateway ports in the same gateway chassis.