Scenario - Using Open vSwitch with DVR

Overview

Operators can choose to utilize Open vSwitch with Distributed Virtual Routing (DVR) instead of Linux Bridges or plain Open vSwitch for the neutron ML2 agent. This offers the possibility to deploy virtual routing instances outside the usual neutron networking node. This document outlines how to set it up in your environment.

Recommended reading

This guide is a variation of the standard Open vSwitch deployment guide available at:

https://docs.openstack.org/openstack-ansible-os_neutron/latest/app-openvswitch.html

We recommend that you read the following documents before proceeding:

• Neutron documentation on Open vSwitch DVR OpenStack deployments: https://docs.openstack.org/neutron/latest/admin/deploy-ovs-ha-dvr.html

• Blog post on how OpenStack-Ansible works with Open vSwitch: https://trumant.github.io/openstack-ansible-dvr-with-openvswitch.html

Prerequisites

Configure your networking according the Open vSwitch setup:

• Scenario - Using Open vSwitch https://docs.openstack.org/openstack-ansible-os_neutron/latest/app-openvswitch.html

OpenStack-Ansible user variables

Create a group var file for your network hosts /etc/openstack_deploy/group_vars/network_hosts. It has to include:

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

Specify provider network definitions in your /etc/openstack_deploy/openstack_user_config.yml that define one or more Neutron provider bridges and related configuration:

Note

Bridges specified here will be created automatically. If network_interface is defined, the interface will be placed into the bridge automatically.

- network:
    container_bridge: "br-provider"
    container_type: "veth"
    type: "vlan"
    range: "101:200,301:400"
    net_name: "physnet1"
    network_interface: "bond1"
    group_binds:
      - neutron_openvswitch_agent
- network:
    container_bridge: "br-provider2"
    container_type: "veth"
    type: "vlan"
    range: "203:203,467:500"
    net_name: "physnet2"
    network_interface: "bond2"
    group_binds:
      - neutron_openvswitch_agent

When using flat provider networks, modify the network type accordingly:

- network:
    container_bridge: "br-provider"
    container_type: "veth"
    type: "flat"
    net_name: "flat"
    group_binds:
      - neutron_openvswitch_agent

Specify an overlay network definition in your /etc/openstack_deploy/openstack_user_config.yml that defines overlay network-related configuration:

Note

The bridge name should correspond to a pre-created Linux bridge or OVS bridge.

- network:
    container_bridge: "br-vxlan"
    container_type: "veth"
    container_interface: "eth10"
    ip_from_q: "tunnel"
    type: "vxlan"
    range: "1:1000"
    net_name: "vxlan"
    group_binds:
      - neutron_openvswitch_agent

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

Note

The only difference a DVR deployment and the standard Open vSwitch deployment is the setting of the respective neutron_plugin_type.

neutron_plugin_type: ml2.ovs.dvr

neutron_ml2_drivers_type: "flat,vlan,vxlan"
neutron_plugin_base:
  - router
  - metering

The overrides are instructing Ansible to deploy the OVS mechanism driver and associated OVS and DVR components. This is done by setting neutron_plugin_type to ml2.ovs.dvr.

The neutron_ml2_drivers_type override provides support for all common type drivers supported by OVS.

For additional information regarding provider network overrides and other configuration options, please refer to the standard Open vSwitch deployment available at:

https://docs.openstack.org/openstack-ansible-os_neutron/latest/app-openvswitch.html