Scenario - OpenDaylight and Open vSwitch

Overview

Deployers can choose to enhance neutron capabilities by means of the OpenDaylight SDN Controller, which works together with Open vSwitch to provide advanced networking capabilities. This document explains how to use them in your environment.

Prerequisites

The OpenDaylight Ansible role needs to be available in Ansible’s role path.

OpenStack-Ansible user variables

Set the following user variables in your /etc/openstack_deploy/user_variables.yml:

### Ensure the openvswitch kernel module is loaded
openstack_host_specific_kernel_modules:
  - name: "openvswitch"
    pattern: "CONFIG_OPENVSWITCH"
    group: "network_hosts"

### Use OpenDaylight SDN Controller
neutron_plugin_type: "ml2.opendaylight"
odl_ip: "{{ hostvars[groups['opendaylight'][0]]['ansible_facts']['default_ipv4']['address'] }}"
neutron_opendaylight_conf_ini_overrides:
  ml2_odl:
    url: "http://{{ odl_ip }}:8180/controller/nb/v2/neutron"
    username: <username>
    password: <password>

Most of the content of this file is self-explanatory. The first block is used to deploy Open vSwitch in all network hosts.

The second block is instructing Ansible to deploy OpenDaylight SDN Controller. This is done by specifying neutron_plugin_type to ml2.opendaylight. The IP address of the OpenDaylight controller needs to be inferred from the deployment configuration as well. That can be used with a line such as the one in the example.

After that, some configuration is needed to integrate OpenDaylight and Neutron, using the ml2_odl section.

  • url: OpenDaylight’s northbound url. This is automatically retrieved from the deployment configuration, so just need to copy the example line.

  • username: OpenDaylight northbound API username

  • password: OpenDaylight northbound API password for <username>

Apart from these options, the deployer might want to change the installation method for OpenDaylight Ansible role. This role uses pre-packaged binaries, which can be either deb or rpm files, and by default it will download these binaries from OpenDaylight repositories, trying to guess the correct package depending on the underlying operating system.

Also, the set of features that will be enabled in the OpenDaylight SDN controller defaults to odl-netvirt-openstack, which is the minimum for an OpenStack integration. The deployer can modify this value by providing a list of feature names in the opendaylight_extra_features variable.

For more information, see OpenDaylight Ansible role documentation.

L3 configuration

L3 services are by default provided by the neutron-l3-agent. ODL is capable of providing L3 services too and if ODL is deployed, it is actually recommended to use them instead of neutron. Remember that L3 services allow, among other things, to give VMs connectivity to the internet.

To activate the ODL L3 services, you should add to the above explained variables:

# Activate the L3 capabilities of ODL
neutron_plugin_base:
 - odl-router_v2
 - metering

If you want to use the L3 capabilities, you will need to define a external Neutron network and set a gateway. Note that the br-vlan interface of the nodes could be a perfect interface for that gateway, although it depends on your network topology.

SFC configuration

It is possible to have an openstack-ansible deployment with SFC capabilities. The following config needs to be added to the above described /etc/openstack_deploy/user_variables.yml :

neutron_plugin_base:
 - router
 - metering
 - flow_classifier
 - sfc

When using this configuration, networking-sfc will be deployed and SFC features will be activated in ODL. A SFC topology could be then set up through the networking-sfc API or through an orchestrator like tacker (if deployed).

BGPVPN configuration

ODL provides support for extending L3 services over DC-GW by BGPVPN. This way Openstack configures ODL as BGP speaker to exchange the routes with DC-GW to establish the communication between Tenant VMs and external world in the data path.

To activate BGPVPN service, you should add the following variables in addition to the OpenStack-Ansible user variables mentioned above.

# Activate the BGPVPN capabilities of ODL
neutron_plugin_base:
 - odl-router_v2
 - bgpvpn

Security information

Communications between the OpenDaylight SDN Controller and Open vSwitch are not secured by default. For further information on securing this interface, see these manuals: