Fast Data Stacks Scenario: os-odl_l2-fdio-ha Overview and Description

Scenario: “OpenStack - Opendaylight (L2) -” (apex-os-odl_l2-fdio-ha) is a scenario developed as part of the FastDataStacks OPNFV project.

1. Scenario: “OpenStack - OpenDaylight (Layer 2) -”

Scenario: apex-os-odl_l2-fdio-ha

“apex-os-odl_l2-fdio-ha” is a scenario developed as part of the FastDataStacks OPNFV project. The main components of the “apex-os-odl_l2-fdio-ha” scenario are:

  • APEX (TripleO) installer (please also see APEX installer documentation)
  • Openstack (in HA configuration)
  • OpenDaylight controller in clustered mode controlling layer 2 networking
  • virtual forwarder for tenant networking

2. Introduction

NFV and virtualized high performance applications, such as video processing, require a “fast data stack” solution that provides both carrier grade forwarding performance, scalability and open extensibility, along with functionality for realizing application policies and controlling a complex network topology.

A solution stack is only as good as its foundation. Key foundational assets for NFV infrastructure are

  • The virtual forwarder: The virtual forwarder needs to be a feature rich, high performance, highly scale virtual switch-router. It needs to leverage hardware accelerators when available and run in user space. In addition, it should be modular and easily extensible.
  • Forwarder diversity: A solution stack should support a variety of forwarders, hardware forwarders (physical switches and routers) as well as software forwarders. This way virtual and physical forwarding domains can be seamlessly glued together.
  • Policy driven connectivity: Connectivity should respect and reflect different business

In order to meet the desired qualities of an NFV infrastructure, the following components were chosen for the “Openstack - OpenDaylight -” scenario:

  • Vector Packet Processor (VPP) - a highly scalable, high performance, extensible virtual forwarder
  • OpenDaylight Controller - an extensible controller platform which offers the ability to separate business logic from networking constructs, supports a diverse set of network devices (virtual and physical) via the “group based policy (GBP)” component, and can be clustered to achieve a highly available deployment - as done in this scenario.

The “Openstack - OpenDaylight -” scenario provides the capability to realize a set of use-cases relevant to the deployment of NFV nodes instantiated by means of an Openstack orchestration system on enabled compute nodes. The role of the Opendaylight network controller in this integration is twofold. It provides a network device configuration and topology abstraction via the Openstack Neutron interface, while providing the capability to realize more complex network policies by means of Group Based Policies. Furthermore it also provides the capabilities to monitor as well as visualize the operation of the virtual network devices and their topologies. In supporting the general use-case of instantiatiting an NFV instance, two specific types of network transport use cases are realized:

  • NFV instances with VPP data-plane forwarding using a VLAN provider network
  • NFV instances with VPP data-plane forwarding using a VXLAN overlay transport network

A deployment of the “apex-os-odl_l2-fdio-ha” scenario consists of 4 or more servers:

  • 1 Jumphost hosting the APEX installer - running the Undercloud
  • 3 Controlhosts, which run the Overcloud as well as OpenDaylight as a network controller. OpenDaylight is deployed in clustered mode and runs on all 3 control nodes.
  • 2 or more Computehosts

Tenant networking leverages Open VSwitch (OVS) is used for all other connectivity, in particular the connectivity to public networking / the Internet (i.e. br-ext) is performed via OVS as in any standard OpenStack deployment. The OpenDaylight network controller is used to setup and manage layer 2 networking for the scenario. Tenant networking can either leverage VXLAN (in which case a full mesh of VXLAN tunnels is created) or VLANs. Layer 3 connectivity for a tenant network is provided centrally via qrouter on the control node. As in a standard OpenStack deployment, the Layer3 agent configures the qrouter and associated rulesets for security (security groups) and NAT (floating IPs). Public IP network connectivity for a tenant network is provided by interconnecting the VPP-based bridge domain representing the tenant network to qrouter using a tap interface. The setup is depicted below:


With high availability factored in the setup looks like the following.


Note that the picture only shows two Controllernodes for reasons of simplicity. A HA deployment will always include 3 Controllernodes.

2.1. Features of the scenario

Main features of the “apex-os-odl_l2-fdio-ha” scenario:

  • Automated installation using the APEX installer
  • Fast and scalable tenant networking using as forwarder
  • Layer 2 networking using VLANs or VXLAN, managed and controlled through OpenDaylight
  • Layer 3 connectivitiy for tenant networks supplied centrally on the Control node through standard OpenStack mechanisms. All layer 3 features apply, including floating IPs (i.e. NAT) and security groups.
  • Manual and automatic (via DHCP) addressing on tenant networks
  • OpenDaylight controller high availability (clustering)
  • OpenStack high availability

3. Scenario components and composition

The apex-os-odl_l2-fdio-ha scenario combines components from three key open source projects: OpenStack, OpenDaylight, and Fast Data ( The key components that realize the apex-os-odl_l2-fdio-ha scenario and which differ from a regular, OVS-based scenario, are the OpenStack ML2 OpenDaylight plugin, OpenDaylight Neutron Northbound, OpenDaylight Group Based Policy, OpenDaylight Virtual Bridge Domain Manager, Honeycomb management agent and Vector Packet Processor (VPP).

Here’s a more detailed list of the individual software components involved:

Openstack Neutron ML2 OpenDaylight Plugin: Handles Neutron data base synchronization and interaction with the southbound controller using a REST interface.

ODL GBP Neutron Mapper: Maps neutron elements like networks, subnets, security groups, etc. to GBP entities: Creates policy and configuration for tenants (endpoints, resolved policies, forwarding rules).

ODL GBP Neutron VPP Mapper: Maps Neutron ports to VPP endpoints in GBP.

ODL GBP Location Manager: Provides real location for endpoints (i.e. Which physical node an endpoint is connected to).

GBP Renderer Manager: Creates configuration for Renderers (like e.g. VPP-Renderer or OVS-Renderer). The GBP Renderer Manager is the central point for dispatching of data to specific device renderers. It uses the information derived from the GBP end-point and its topology entries to dispatch the task of configuration to a specific device renderer by writing a renderer policy configuration into the registered renderer’s policy store. The renderer manager also monitors, by being a data change listener on the VPP Renderer Policy States, for any errors in the application of a rendered configuration.

GBP VPP Renderer Interface Manager: Listens to VPP endpoints in the Config DataStore and configures associated interfaces on VPP via HoneyComb.

GBP VPP Renderer Renderer Policy Manager: Manages the creation of bridge domains using VBD and assigns interfaces to bridge domains.

Virtual Bridge Domain Manager (VBD): Creates bridge domains (i.e. in case of VXLAN creates full mesh of VXLAN tunnels, configures split horizon on tunnel endpoints etc.). VDB configures VXLAN tunnels always into a full-mesh with split-horizon group forwarding applied on any domain facing tunnel interface (i.e. forwarding behavior will be that used for VPLS).

Virtual Packet Processor (VPP) and Honeycomb server: The VPP is the accelerated data plane forwarding engine relying on vhost user interfaces towards Virtual Machines created by the Nova Agent. The Honeycomb NETCONF configuration server is responsible for driving the configuration of the VPP, and collecting the operational data.

Nova Agent: The Nova Agent, a sub-component of the overall Openstack architecture, is responsible for interacting with the compute node’s host Libvirt API to drive the life-cycle of Virtual Machines. It, along with the compute node software, are assumed to be capable of supporting vhost user interfaces.

The picture below shows the key components.


To provide a better understanding how the above mentioned components interact with each other, the following diagram shows how the example of creating a vhost-user port on VPP through Openstack Neutron:

To create or update a port, Neutron will send a request to ODL Neutron Northbound which contains the UUID, along with the host-id as “vpp” and vif-type as “vhost-user”. The GBP Neutron mapper turns the “Neutron speak” of “ports” into the generic connectivity model that GroupBasedPolicy uses. Neutron “ports” become generic “GBP Endpoints” which can be consumed by the GBP Renderer Manager. The GBP Renderer Manager resolves the policy for the endpoint, i.e. it determines which communication relationships apply to the specific endpoint, and hands the resolution to a device specific renderer, which is the VPP renderer in the given case here. VPP renderer turns the generic policy into VPP specific configuration. Note that in case the policy would need to be applied to a different device, e.g. an OpenVSwitch (OVS), then an “OVS Renderer” would be used. VPP Renderer and the topology manager (“Virtual Bridge Domain” manager - i.e. VBD) cooperate to create the actual network configuration. VPP Renderer configures the interfaces to the virtual machines (VM), i.e. the vhost-user interface in the given case here and attaches them to a bridge domain on VPP. VBD handles the setup of connectivity between bridge domains on individual VPPs, i.e. it maintains the VXLAN tunnels in the given case here. Both VPP Renderer as well as VBD communicate with the device through Netconf/YANG. All compute and control nodes run an instance of VPP and the VPP-configuration agent “Honeycomb”. Honeycomb serves as a Netconf/YANG server, receives the configuration commands from VBD and VPP Renderer and drives VPP configuration using VPP’s local Java APIs.


4. Scenario Configuration

To enable the “apex-os-odl_l2-fdio-ha” scenario check the appropriate settings in the APEX configuration files. Those are typically found in /etc/opnfv-apex.

File “deploy_settings.yaml” choose opendaylight as controller with version “carbon” and enable vpp as forwarder. Also make sure that you set “ha_enabled” to “true” in the global_params section. “ha_enabled” is the only real difference from a configuration file perspective between the scenario with high availability when compared to the ODL-L2 scenario without high-availability support. “hugepages” need to set to a sufficiently large value for VPP to work. The default value for VPP is 1024, but this only allows for a few VMs to be started. If feasible, choose a significantly larger number on the compute nodes:

  ha_enabled: true

  sdn_controller: opendaylight
  sdn_l3: false
  odl_version: carbon
  tacker: true
  congress: true
  sfc: false
  vpn: false
  vpp: true
  dataplane: fdio
        hugepages: 1024
        hugepagesz: 2M
        intel_iommu: 'on'
        iommu: pt
        isolcpus: 1,2
        main-core: 1
        corelist-workers: 2
        uio-driver: uio_pci_generic
        hugepagesz: 2M
        hugepages: 2048
        intel_iommu: 'on'
        iommu: pt
        isolcpus: 1,2
        main-core: 1
        corelist-workers: 2
        uio-driver: uio_pci_generic

5. Validated deployment environments

The “os-odl_l2-fdio-ha” scenario has been deployed and tested on the following sets of hardware:

6. Limitations, Issues and Workarounds

For specific information on limitations and issues, please refer to the APEX installer release notes. Note that this high availability scenario deploys OpenStack in HA mode and OpenDaylight in cluster mode.

7. References