- OpenStack Neutron has faced issues with scalability and single points of failure that have led many users to rely on external network controllers instead of Neutron alone. - OpenDaylight is an open source SDN platform that provides network abstractions and frameworks for programming network elements. It has emerged as a popular external network controller integrated with Neutron deployments. - In the Icehouse release, OpenStack integrated OpenDaylight through a mechanism driver to connect Neutron to OpenDaylight for network provisioning using technologies like VxLAN and GRE. This allows Neutron to leverage OpenDaylight's capabilities for improved scalability and reliability.

1. OpenStack Neutron and
OpenDaylight
Ramkumar Gowrishankar

2. OS Neutron and Controllers
• Personal views from attending the summit
– Networking in OS has kind of been neglected but is a critical
piece for success of cloud orchestration (people still using nova-
network because of lack of features in neutron).
– OS Neutron scalability issues and single point of failure with the
Network Node seems to be major pain point of community.
– Neutron implementation in OpenStack is a reference
implementation and not meant to scale.
– Think of neutron as providing a common API similar to what
nova does and not a network controller in itself.
– Talking to integrators: Any deployment of scale (>1000VMs)
needs a controller because neutron cannot handle the scale.
– Integration with NSX or Ryu or Contrail seemed most common
in deployment today.

3. OpenDaylight
• Open Source SDN platform designed to provide a
modular framework to program network
elements (Both virtual and physical)
• Collaborative project under the Linux Foundation
• ODL provides:
– common abstractions of capabilities via NorthBound
API
– framework to implement business logic for
programming network elements
– standard and custom south-bound APIs to connect to
network elements

4. Controller Architecture
www.opendaylight.org
Go to: http://www.ietf.org/proceedings/88/slides/slides-88-netconf-3.pdf for more
detailed architecture diagram

5. ODL and OS – match made in heaven?
• ODL is a OpenSource project much like OS
– Emerged from the need for an OpenSource
alternative to walled gardens
• Vibrant developer community that is
expanding
• Lot of developer interaction between the OS-
Neutron and ODL community.
• Lot of companies involved actively in both
projects

6. OS-ODL integration in IceHouse
• ML2 mechanism driver in
OpenStack IceHouse to
connect to ODL (support
for VxLAN and GRE)
• Neutron Service: Common
shim that receives the
messages
• In Hydrogen release, 3
plugins consume the data.
– Only one of the 3 can be
actively running.
https://www.openstack.org/assets/presentation-media/osodlatl.pdf

7. Sample architecture with OVSDB
http://networkstatic.net/opendaylight-openstack-integration-devstack-fedora-20/

8. Questions
If interested: Local meetup group on OpenDaylight (rtp-opendaylight)
Resources: www.opendaylight.org