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Taikun OCP Guide

Table of Contents

BGP dynamic routing

BGP dynamic routing enables advertisement of self-service (private)
network prefixes to physical network devices that support BGP such as
routers, thus removing the conventional dependency on static routes. The
feature relies on address scopes <config-address-scopes> and
requires knowledge of their operation for proper deployment.

BGP dynamic routing consists of a service plug-in and an agent. The
service plug-in implements the Networking service extension and the
agent manages BGP peering sessions. A cloud administrator creates and
configures a BGP speaker using the CLI or API and manually schedules it
to one or more hosts running the agent. Agents can reside on hosts with
or without other Networking service agents. Prefix advertisement depends
on the binding of external networks to a BGP speaker and the address
scope of external and internal IP address ranges or subnets.

BGP dynamic routing overview

Note

Although self-service networks generally use private IP address
ranges (RFC1918) for IPv4 subnets, BGP dynamic routing can advertise any
IPv4 address ranges.

Example configuration

The example configuration involves the following components:

  • One BGP agent.
  • One address scope containing IP address range 203.0.113.0/24 for
    provider networks, and IP address ranges 192.0.2.0/25 and 192.0.2.128/25
    for self-service networks.
  • One provider network using IP address range 203.0.113.0/24.
  • Three self-service networks.
    • Self-service networks 1 and 2 use IP address ranges inside of the
      address scope.
    • Self-service network 3 uses a unique IP address range
      198.51.100.0/24 to demonstrate that the BGP speaker does not advertise
      prefixes outside of address scopes.
  • Three routers. Each router connects one self-service network to the
    provider network.

    • Router 1 contains IP addresses 203.0.113.11 and 192.0.2.1
    • Router 2 contains IP addresses 203.0.113.12 and 192.0.2.129
    • Router 3 contains IP addresses 203.0.113.13 and 198.51.100.1
  • One preexisting peering network 10.0.0.0/24 on the host running the
    neutron BGP dynamic routing agent to facilitate BGP communication with
    its peer. 10.0.0.1 is the address for the host and 10.0.0.2 the address
    for the peer.

Note

The example configuration assumes sufficient knowledge about the
Networking service, routing, and BGP. For basic deployment of the
Networking service, consult one of the deploy. For more information on BGP, see RFC 4271.

Controller node

  • In the neutron.conf file, enable the conventional
    layer-3 and BGP dynamic routing service plug-ins:

    [DEFAULT]
    service_plugins = neutron_dynamic_routing.services.bgp.bgp_plugin.BgpPlugin,neutron.services.l3_router.l3_router_plugin.L3RouterPlugin

Agent nodes

  • In the bgp_dragent.ini file:
    • Configure the driver.

      [BGP]
      bgp_speaker_driver = neutron_dynamic_routing.services.bgp.agent.driver.os_ken.driver.OsKenBgpDriver

      Note

      The agent currently only supports the os-ken BGP driver.

    • Configure the router ID.

      [BGP]
      bgp_router_id = ROUTER_ID

      Replace ROUTER_ID with a suitable unique 32-bit number,
      typically an IPv4 address on the host running the agent. For example,
      10.0.0.1.

Verify service operation

  1. Source the administrative project credentials.

  2. Verify presence and operation of each BGP dynamic routing
    agent.

    $ openstack network agent list --agent-type bgp
    +--------------------------------------+---------------------------+------------+-------------------+-------+-------+---------------------+
    | ID                                   | Agent Type                | Host       | Availability Zone | Alive | State | Binary              |
    +--------------------------------------+---------------------------+------------+-------------------+-------+-------+---------------------+
    | 37729181-2224-48d8-89ef-16eca8e2f77e | BGP dynamic routing agent | controller | None              | :-)   | UP    | neutron-bgp-dragent |
    +--------------------------------------+---------------------------+------------+-------------------+-------+-------+---------------------+

Create the address
scope and subnet pools

  1. Create an address scope. The provider (external) and self-service
    networks must belong to the same address scope for the agent to
    advertise those self-service network prefixes.

    $ openstack address scope create --share --ip-version 4 bgp
    
    +------------+--------------------------------------+
    | Field      | Value                                |
    +------------+--------------------------------------+
    | headers    |                                      |
    | id         | f71c958f-dbe8-49a2-8fb9-19c5f52a37f1 |
    | ip_version | 4                                    |
    | name       | bgp                                  |
    | project_id | 86acdbd1d72745fd8e8320edd7543400     |
    | shared     | True                                 |
    +------------+--------------------------------------+
  2. Create subnet pools. The provider and self-service networks use
    different pools.

    • Create the provider network pool.

      $ openstack subnet pool create --pool-prefix 203.0.113.0/24 \
        --address-scope bgp provider
      
      +-------------------+--------------------------------------+
      | Field             | Value                                |
      +-------------------+--------------------------------------+
      | address_scope_id  | f71c958f-dbe8-49a2-8fb9-19c5f52a37f1 |
      | created_at        | 2017-01-12T14:58:57Z                 |
      | default_prefixlen | 8                                    |
      | default_quota     | None                                 |
      | description       |                                      |
      | headers           |                                      |
      | id                | 63532225-b9a0-445a-9935-20a15f9f68d1 |
      | ip_version        | 4                                    |
      | is_default        | False                                |
      | max_prefixlen     | 32                                   |
      | min_prefixlen     | 8                                    |
      | name              | provider                             |
      | prefixes          | 203.0.113.0/24                       |
      | project_id        | 86acdbd1d72745fd8e8320edd7543400     |
      | revision_number   | 1                                    |
      | shared            | False                                |
      | tags              | []                                   |
      | updated_at        | 2017-01-12T14:58:57Z                 |
      +-------------------+--------------------------------------+
    • Create the self-service network pool.

      $ openstack subnet pool create --pool-prefix 192.0.2.0/25 \
        --pool-prefix 192.0.2.128/25 --address-scope bgp \
        --share selfservice
      
      +-------------------+--------------------------------------+
      | Field             | Value                                |
      +-------------------+--------------------------------------+
      | address_scope_id  | f71c958f-dbe8-49a2-8fb9-19c5f52a37f1 |
      | created_at        | 2017-01-12T15:02:31Z                 |
      | default_prefixlen | 8                                    |
      | default_quota     | None                                 |
      | description       |                                      |
      | headers           |                                      |
      | id                | 8d8270b1-b194-4b7e-914c-9c741dcbd49b |
      | ip_version        | 4                                    |
      | is_default        | False                                |
      | max_prefixlen     | 32                                   |
      | min_prefixlen     | 8                                    |
      | name              | selfservice                          |
      | prefixes          | 192.0.2.0/25, 192.0.2.128/25         |
      | project_id        | 86acdbd1d72745fd8e8320edd7543400     |
      | revision_number   | 1                                    |
      | shared            | True                                 |
      | tags              | []                                   |
      | updated_at        | 2017-01-12T15:02:31Z                 |
      +-------------------+--------------------------------------+

Create the
provider and self-service networks

  1. Create the provider network.

    $ openstack network create provider --external --provider-physical-network \
      provider --provider-network-type flat
    Created a new network:
    +---------------------------+--------------------------------------+
    | Field                     | Value                                |
    +---------------------------+--------------------------------------+
    | admin_state_up            | UP                                   |
    | availability_zone_hints   |                                      |
    | availability_zones        |                                      |
    | created_at                | 2016-12-21T08:47:41Z                 |
    | description               |                                      |
    | headers                   |                                      |
    | id                        | 190ca651-2ee3-4a4b-891f-dedda47974fe |
    | ipv4_address_scope        | None                                 |
    | ipv6_address_scope        | None                                 |
    | is_default                | False                                |
    | mtu                       | 1450                                 |
    | name                      | provider                             |
    | port_security_enabled     | True                                 |
    | project_id                | c961a8f6d3654657885226378ade8220     |
    | provider:network_type     | flat                                 |
    | provider:physical_network | provider                             |
    | provider:segmentation_id  | 66                                   |
    | revision_number           | 3                                    |
    | router:external           | External                             |
    | shared                    | False                                |
    | status                    | ACTIVE                               |
    | subnets                   |                                      |
    | tags                      | []                                   |
    | updated_at                | 2016-12-21T08:47:41Z                 |
    +---------------------------+--------------------------------------+
  2. Create a subnet on the provider network using an IP address range
    from the provider subnet pool.

    $ openstack subnet create --subnet-pool provider \
      --prefix-length 24 --gateway 203.0.113.1 --network provider \
      --allocation-pool start=203.0.113.11,end=203.0.113.254 provider
    +-------------------+--------------------------------------+
    | Field             | Value                                |
    +-------------------+--------------------------------------+
    | allocation_pools  | 203.0.113.11-203.0.113.254           |
    | cidr              | 203.0.113.0/24                       |
    | created_at        | 2016-03-17T23:17:16                  |
    | description       |                                      |
    | dns_nameservers   |                                      |
    | enable_dhcp       | True                                 |
    | gateway_ip        | 203.0.113.1                          |
    | host_routes       |                                      |
    | id                | 8ed65d41-2b2a-4f3a-9f92-45adb266e01a |
    | ip_version        | 4                                    |
    | ipv6_address_mode | None                                 |
    | ipv6_ra_mode      | None                                 |
    | name              | provider                             |
    | network_id        | 68ec148c-181f-4656-8334-8f4eb148689d |
    | project_id        | b3ac05ef10bf441fbf4aa17f16ae1e6d     |
    | segment_id        | None                                 |
    | service_types     |                                      |
    | subnetpool_id     | 3771c0e7-7096-46d3-a3bd-699c58e70259 |
    | tags              |                                      |
    | updated_at        | 2016-03-17T23:17:16                  |
    +-------------------+--------------------------------------+

    Note

    The IP address allocation pool starting at .11 improves
    clarity of the diagrams. You can safely omit it.

  3. Create the self-service networks.

    $ openstack network create selfservice1
    Created a new network:
    +---------------------------+--------------------------------------+
    | Field                     | Value                                |
    +---------------------------+--------------------------------------+
    | admin_state_up            | UP                                   |
    | availability_zone_hints   |                                      |
    | availability_zones        |                                      |
    | created_at                | 2016-12-21T08:49:38Z                 |
    | description               |                                      |
    | headers                   |                                      |
    | id                        | 9d842606-ef3d-4160-9ed9-e03fa63aed96 |
    | ipv4_address_scope        | None                                 |
    | ipv6_address_scope        | None                                 |
    | mtu                       | 1450                                 |
    | name                      | selfservice1                         |
    | port_security_enabled     | True                                 |
    | project_id                | c961a8f6d3654657885226378ade8220     |
    | provider:network_type     | vxlan                                |
    | provider:physical_network | None                                 |
    | provider:segmentation_id  | 106                                  |
    | revision_number           | 3                                    |
    | router:external           | Internal                             |
    | shared                    | False                                |
    | status                    | ACTIVE                               |
    | subnets                   |                                      |
    | tags                      | []                                   |
    | updated_at                | 2016-12-21T08:49:38Z                 |
    +---------------------------+--------------------------------------+
    
    $ openstack network create selfservice2
    Created a new network:
    +---------------------------+--------------------------------------+
    | Field                     | Value                                |
    +---------------------------+--------------------------------------+
    | admin_state_up            | UP                                   |
    | availability_zone_hints   |                                      |
    | availability_zones        |                                      |
    | created_at                | 2016-12-21T08:50:05Z                 |
    | description               |                                      |
    | headers                   |                                      |
    | id                        | f85639e1-d23f-438e-b2b1-f40570d86b1c |
    | ipv4_address_scope        | None                                 |
    | ipv6_address_scope        | None                                 |
    | mtu                       | 1450                                 |
    | name                      | selfservice2                         |
    | port_security_enabled     | True                                 |
    | project_id                | c961a8f6d3654657885226378ade8220     |
    | provider:network_type     | vxlan                                |
    | provider:physical_network | None                                 |
    | provider:segmentation_id  | 21                                   |
    | revision_number           | 3                                    |
    | router:external           | Internal                             |
    | shared                    | False                                |
    | status                    | ACTIVE                               |
    | subnets                   |                                      |
    | tags                      | []                                   |
    | updated_at                | 2016-12-21T08:50:05Z                 |
    +---------------------------+--------------------------------------+
    
    $ openstack network create selfservice3
    Created a new network:
    +---------------------------+--------------------------------------+
    | Field                     | Value                                |
    +---------------------------+--------------------------------------+
    | admin_state_up            | UP                                   |
    | availability_zone_hints   |                                      |
    | availability_zones        |                                      |
    | created_at                | 2016-12-21T08:50:35Z                 |
    | description               |                                      |
    | headers                   |                                      |
    | id                        | eeccdb82-5cf4-4999-8ab3-e7dc99e7d43b |
    | ipv4_address_scope        | None                                 |
    | ipv6_address_scope        | None                                 |
    | mtu                       | 1450                                 |
    | name                      | selfservice3                         |
    | port_security_enabled     | True                                 |
    | project_id                | c961a8f6d3654657885226378ade8220     |
    | provider:network_type     | vxlan                                |
    | provider:physical_network | None                                 |
    | provider:segmentation_id  | 86                                   |
    | revision_number           | 3                                    |
    | router:external           | Internal                             |
    | shared                    | False                                |
    | status                    | ACTIVE                               |
    | subnets                   |                                      |
    | tags                      | []                                   |
    | updated_at                | 2016-12-21T08:50:35Z                 |
    +---------------------------+--------------------------------------+
  4. Create a subnet on the first two self-service networks using an
    IP address range from the self-service subnet pool.

    $ openstack subnet create --network selfservice1 --subnet-pool selfservice \
      --prefix-length 25 selfservice1
    +-------------------+----------------------------------------------------+
    | Field             | Value                                              |
    +-------------------+----------------------------------------------------+
    | allocation_pools  | 192.0.2.2-192.0.2.127                              |
    | cidr              | 192.0.2.0/25                                       |
    | created_at        | 2016-03-17T23:20:20                                |
    | description       |                                                    |
    | dns_nameservers   |                                                    |
    | enable_dhcp       | True                                               |
    | gateway_ip        | 198.51.100.1                                       |
    | host_routes       |                                                    |
    | id                | 8edd3dc2-df40-4d71-816e-a4586d61c809               |
    | ip_version        | 4                                                  |
    | ipv6_address_mode |                                                    |
    | ipv6_ra_mode      |                                                    |
    | name              | selfservice1                                       |
    | network_id        | be79de1e-5f56-11e6-9dfb-233e41cec48c               |
    | project_id        | b3ac05ef10bf441fbf4aa17f16ae1e6d                   |
    | revision_number   | 1                                                  |
    | subnetpool_id     | c7e9737a-cfd3-45b5-a861-d1cee1135a92               |
    | tags              | []                                                 |
    | tenant_id         | b3ac05ef10bf441fbf4aa17f16ae1e6d                   |
    | updated_at        | 2016-03-17T23:20:20                                |
    +-------------------+----------------------------------------------------+
    
    $ openstack subnet create --network selfservice2 --subnet-pool selfservice \
      --prefix-length 25 selfservice2
    +-------------------+------------------------------------------------+
    | Field             | Value                                          |
    +-------------------+------------------------------------------------+
    | allocation_pools  | 192.0.2.130-192.0.2.254                        |
    | cidr              | 192.0.2.128/25                                 |
    | created_at        | 2016-03-17T23:20:20                            |
    | description       |                                                |
    | dns_nameservers   |                                                |
    | enable_dhcp       | True                                           |
    | gateway_ip        | 192.0.2.129                                    |
    | host_routes       |                                                |
    | id                | 8edd3dc2-df40-4d71-816e-a4586d61c809           |
    | ip_version        | 4                                              |
    | ipv6_address_mode |                                                |
    | ipv6_ra_mode      |                                                |
    | name              | selfservice2                                   |
    | network_id        | c1fd9846-5f56-11e6-a8ac-0f998d9cc0a2           |
    | project_id        | b3ac05ef10bf441fbf4aa17f16ae1e6d               |
    | revision_number   | 1                                              |
    | subnetpool_id     | c7e9737a-cfd3-45b5-a861-d1cee1135a92           |
    | tags              | []                                             |
    | tenant_id         | b3ac05ef10bf441fbf4aa17f16ae1e6d               |
    | updated_at        | 2016-03-17T23:20:20                            |
    +-------------------+------------------------------------------------+
  5. Create a subnet on the last self-service network using an IP
    address range outside of the address scope.

    $ openstack subnet create --network selfservice3 --prefix 198.51.100.0/24 subnet3
    +-------------------+----------------------------------------------------+
    | Field             | Value                                              |
    +-------------------+----------------------------------------------------+
    | allocation_pools  | 198.51.100.2-198.51.100.254                        |
    | cidr              | 198.51.100.0/24                                    |
    | created_at        | 2016-03-17T23:20:20                                |
    | description       |                                                    |
    | dns_nameservers   |                                                    |
    | enable_dhcp       | True                                               |
    | gateway_ip        | 198.51.100.1                                       |
    | host_routes       |                                                    |
    | id                | cd9f9156-5f59-11e6-aeec-172ec7ee939a               |
    | ip_version        | 4                                                  |
    | ipv6_address_mode |                                                    |
    | ipv6_ra_mode      |                                                    |
    | name              | selfservice3                                       |
    | network_id        | c283dc1c-5f56-11e6-bfb6-efc30e1eb73b               |
    | project_id        | b3ac05ef10bf441fbf4aa17f16ae1e6d                   |
    | revision_number   | 1                                                  |
    | subnetpool_id     |                                                    |
    | tags              | []                                                 |
    | tenant_id         | b3ac05ef10bf441fbf4aa17f16ae1e6d                   |
    | updated_at        | 2016-03-17T23:20:20                                |
    +-------------------+----------------------------------------------------+

Create and configure the
routers

  1. Create the routers.

    $ openstack router create router1
    +-------------------------+--------------------------------------+
    | Field                   | Value                                |
    +-------------------------+--------------------------------------+
    | admin_state_up          | UP                                   |
    | availability_zone_hints |                                      |
    | availability_zones      |                                      |
    | created_at              | 2017-01-10T13:15:19Z                 |
    | description             |                                      |
    | distributed             | False                                |
    | external_gateway_info   | null                                 |
    | flavor_id               | None                                 |
    | ha                      | False                                |
    | headers                 |                                      |
    | id                      | 3f6f4ef8-63be-11e6-bbb3-2fbcef363ab8 |
    | name                    | router1                              |
    | project_id              | b3ac05ef10bf441fbf4aa17f16ae1e6d     |
    | revision_number         | 1                                    |
    | routes                  |                                      |
    | status                  | ACTIVE                               |
    | tags                    | []                                   |
    | updated_at              | 2017-01-10T13:15:19Z                 |
    +-------------------------+--------------------------------------+
    
    $ openstack router create router2
    +-------------------------+--------------------------------------+
    | Field                   | Value                                |
    +-------------------------+--------------------------------------+
    | admin_state_up          | UP                                   |
    | availability_zone_hints |                                      |
    | availability_zones      |                                      |
    | created_at              | 2017-01-10T13:15:19Z                 |
    | description             |                                      |
    | distributed             | False                                |
    | external_gateway_info   | null                                 |
    | flavor_id               | None                                 |
    | ha                      | False                                |
    | headers                 |                                      |
    | id                      | 3fd21a60-63be-11e6-9c95-5714c208c499 |
    | name                    | router2                              |
    | project_id              | b3ac05ef10bf441fbf4aa17f16ae1e6d     |
    | revision_number         | 1                                    |
    | routes                  |                                      |
    | status                  | ACTIVE                               |
    | tags                    | []                                   |
    | updated_at              | 2017-01-10T13:15:19Z                 |
    +-------------------------+--------------------------------------+
    
    $ openstack router create router3
    +-------------------------+--------------------------------------+
    | Field                   | Value                                |
    +-------------------------+--------------------------------------+
    | admin_state_up          | UP                                   |
    | availability_zone_hints |                                      |
    | availability_zones      |                                      |
    | created_at              | 2017-01-10T13:15:19Z                 |
    | description             |                                      |
    | distributed             | False                                |
    | external_gateway_info   | null                                 |
    | flavor_id               | None                                 |
    | ha                      | False                                |
    | headers                 |                                      |
    | id                      | 40069a4c-63be-11e6-9ecc-e37c1eaa7e84 |
    | name                    | router3                              |
    | project_id              | b3ac05ef10bf441fbf4aa17f16ae1e6d     |
    | revision_number         | 1                                    |
    | routes                  |                                      |
    | status                  | ACTIVE                               |
    | tags                    | []                                   |
    | updated_at              | 2017-01-10T13:15:19Z                 |
    +-------------------------+--------------------------------------+
  2. For each router, add one self-service subnet as an interface on
    the router.

    $ openstack router add subnet router1 selfservice1
    
    $ openstack router add subnet router2 selfservice2
    
    $ openstack router add subnet router3 selfservice3
  3. Add the provider network as a gateway on each router.

    $ openstack router set --external-gateway provider router1
    
    $ openstack router set --external-gateway provider router2
    
    $ openstack router set --external-gateway provider router3

Create and configure the
BGP speaker

The BGP speaker advertises the next-hop IP address for eligible
self-service networks and floating IP addresses for instances using
those networks.

  1. Create the BGP speaker.

    $ openstack bgp speaker create --ip-version 4 \
      --local-as LOCAL_AS bgpspeaker
    Created a new bgp_speaker:
    +-----------------------------------+--------------------------------------+
    | Field                             | Value                                |
    +-----------------------------------+--------------------------------------+
    | advertise_floating_ip_host_routes | True                                 |
    | advertise_tenant_networks         | True                                 |
    | id                                | 5f227f14-4f46-4eca-9524-fc5a1eabc358 |
    | ip_version                        | 4                                    |
    | local_as                          | 1234                                 |
    | name                              | bgpspeaker                           |
    | networks                          |                                      |
    | peers                             |                                      |
    | tenant_id                         | b3ac05ef10bf441fbf4aa17f16ae1e6d     |
    +-----------------------------------+--------------------------------------+

    Replace LOCAL_AS with an appropriate local autonomous
    system number. The example configuration uses AS 1234.

  2. A BGP speaker requires association with a provider network to
    determine eligible prefixes. The association builds a list of all
    virtual routers with gateways on provider and self-service networks in
    the same address scope so the BGP speaker can advertise self-service
    network prefixes with the corresponding router as the next-hop IP
    address. Associate the BGP speaker with the provider network.

    $ openstack bgp speaker add network bgpspeaker provider
    Added network provider to BGP speaker bgpspeaker.
  3. Verify association of the provider network with the BGP
    speaker.

    $ openstack bgp speaker show bgpspeaker
    +-----------------------------------+--------------------------------------+
    | Field                             | Value                                |
    +-----------------------------------+--------------------------------------+
    | advertise_floating_ip_host_routes | True                                 |
    | advertise_tenant_networks         | True                                 |
    | id                                | 5f227f14-4f46-4eca-9524-fc5a1eabc358 |
    | ip_version                        | 4                                    |
    | local_as                          | 1234                                 |
    | name                              | bgpspeaker                           |
    | networks                          | 68ec148c-181f-4656-8334-8f4eb148689d |
    | peers                             |                                      |
    | tenant_id                         | b3ac05ef10bf441fbf4aa17f16ae1e6d     |
    +-----------------------------------+--------------------------------------+
  4. Verify the prefixes and next-hop IP addresses that the BGP
    speaker advertises.

    $ openstack bgp speaker list advertised routes bgpspeaker
    +-----------------+--------------+
    | Destination     | Nexthop      |
    +-----------------+--------------+
    | 192.0.2.0/25    | 203.0.113.11 |
    | 192.0.2.128/25  | 203.0.113.12 |
    +-----------------+--------------+
  5. Create a BGP peer.

    $ openstack bgp peer create --peer-ip 10.0.0.2 \
      --remote-as REMOTE_AS bgppeer
    Created a new bgp_peer:
    +-----------+--------------------------------------+
    | Field     | Value                                |
    +-----------+--------------------------------------+
    | auth_type | none                                 |
    | id        | 35c89ca0-ac5a-4298-a815-0b073c2362e9 |
    | name      | bgppeer                              |
    | peer_ip   | 10.0.0.2                             |
    | remote_as | 4321                                 |
    | tenant_id | b3ac05ef10bf441fbf4aa17f16ae1e6d     |
    +-----------+--------------------------------------+

    Replace REMOTE_AS with an appropriate remote autonomous
    system number. The example configuration uses AS 4321 which triggers
    EBGP peering.

    Note

    The host containing the BGP agent must have layer-3 connectivity to
    the provider router.

  6. Add a BGP peer to the BGP speaker.

    $ openstack bgp speaker add peer bgpspeaker bgppeer
    Added BGP peer bgppeer to BGP speaker bgpspeaker.
  7. Verify addition of the BGP peer to the BGP speaker.

    $ openstack bgp speaker show bgpspeaker
    +-----------------------------------+--------------------------------------+
    | Field                             | Value                                |
    +-----------------------------------+--------------------------------------+
    | advertise_floating_ip_host_routes | True                                 |
    | advertise_tenant_networks         | True                                 |
    | id                                | 5f227f14-4f46-4eca-9524-fc5a1eabc358 |
    | ip_version                        | 4                                    |
    | local_as                          | 1234                                 |
    | name                              | bgpspeaker                           |
    | networks                          | 68ec148c-181f-4656-8334-8f4eb148689d |
    | peers                             | 35c89ca0-ac5a-4298-a815-0b073c2362e9 |
    | tenant_id                         | b3ac05ef10bf441fbf4aa17f16ae1e6d     |
    +-----------------------------------+--------------------------------------+

    Note

    After creating a peering session, you cannot change the local or
    remote autonomous system numbers.

Schedule the BGP speaker
to an agent

  1. Unlike most agents, BGP speakers require manual scheduling to an
    agent. BGP speakers only form peering sessions and begin prefix
    advertisement after scheduling to an agent. Schedule the BGP speaker to
    agent 37729181-2224-48d8-89ef-16eca8e2f77e.

    $ openstack bgp dragent add speaker 37729181-2224-48d8-89ef-16eca8e2f77e bgpspeaker
    Associated BGP speaker bgpspeaker to the Dynamic Routing agent.
  2. Verify scheduling of the BGP speaker to the agent.

    $ openstack bgp dragent list --bgp-speaker bgpspeaker
    +--------------------------------------+------------+-------+-------+
    | ID                                   | Host       | State | Alive |
    +--------------------------------------+------------+-------+-------+
    | 37729181-2224-48d8-89ef-16eca8e2f77e | controller | True  | :-)   |
    +--------------------------------------+------------+-------+-------+

Prefix advertisement

BGP dynamic routing advertises prefixes for self-service networks and
host routes for floating IP addresses.

Advertisement of a self-service network requires satisfying the
following conditions:

  • The external and self-service network reside in the same address
    scope.
  • The router contains an interface on the self-service subnet and a
    gateway on the external network.
  • The BGP speaker associates with the external network that provides a
    gateway on the router.
  • The BGP speaker has the advertise_tenant_networks
    attribute set to True.

Example of prefix advertisements with self-service networks

Advertisement of a floating IP address requires satisfying the
following conditions:

  • The router with the floating IP address binding contains a gateway
    on an external network with the BGP speaker association.
  • The BGP speaker has the
    advertise_floating_ip_host_routes attribute set to
    True.

Example of prefix advertisements with floating IP addresses

Operation with
Distributed Virtual Routers (DVR)

For both floating IP and IPv4 fixed IP addresses, the BGP speaker
advertises the floating IP agent gateway on the corresponding compute
node as the next-hop IP address. When using IPv6 fixed IP addresses, the
BGP speaker advertises the DVR SNAT node as the next-hop IP address.

For example, consider the following components:

  1. A provider network using IP address range 203.0.113.0/24, and
    supporting floating IP addresses 203.0.113.101, 203.0.113.102, and
    203.0.113.103.
  2. A self-service network using IP address range 198.51.100.0/24.
  3. Instances with fixed IP’s 198.51.100.11, 198.51.100.12, and
    198.51.100.13
  4. The SNAT gateway resides on 203.0.113.11.
  5. The floating IP agent gateways (one per compute node) reside on
    203.0.113.12, 203.0.113.13, and 203.0.113.14.
  6. Three instances, one per compute node, each with a floating IP
    address.
  7. advertise_tenant_networks is set to False
    on the BGP speaker
$ openstack bgp speaker list advertised routes bgpspeaker
+------------------+--------------+
| Destination      | Nexthop      |
+------------------+--------------+
| 198.51.100.0/24  | 203.0.113.11 |
| 203.0.113.101/32 | 203.0.113.12 |
| 203.0.113.102/32 | 203.0.113.13 |
| 203.0.113.103/32 | 203.0.113.14 |
+------------------+--------------+

When floating IP’s are disassociated and
advertise_tenant_networks is set to True, the
following routes will be advertised:

$ openstack bgp speaker list advertised routes bgpspeaker
+------------------+--------------+
| Destination      | Nexthop      |
+------------------+--------------+
| 198.51.100.0/24  | 203.0.113.11 |
| 198.51.100.11/32 | 203.0.113.12 |
| 198.51.100.12/32 | 203.0.113.13 |
| 198.51.100.13/32 | 203.0.113.14 |
+------------------+--------------+

You can also identify floating IP agent gateways in your environment
to assist with verifying operation of the BGP speaker.

$ openstack port list --device-owner network:floatingip_agent_gateway
+--------------------------------------+------+-------------------+--------------------------------------------------------------------------------------------------------+
| ID                                   | Name | MAC Address       | Fixed IP Addresses                                                                                     |
+--------------------------------------+------+-------------------+--------------------------------------------------------------------------------------------------------+
| 87cf2970-4970-462e-939e-00e808295dfa |      | fa:16:3e:7c:68:e3 | ip_address='203.0.113.12', subnet_id='8ed65d41-2b2a-4f3a-9f92-45adb266e01a'                            |
| 8d218440-0d2e-49d0-8a7b-3266a6146dc1 |      | fa:16:3e:9d:78:cf | ip_address='203.0.113.13', subnet_id='8ed65d41-2b2a-4f3a-9f92-45adb266e01a'                            |
| 87cf2970-4970-462e-939e-00e802281dfa |      | fa:16:3e:6b:18:e0 | ip_address='203.0.113.14', subnet_id='8ed65d41-2b2a-4f3a-9f92-45adb266e01a'                            |
+--------------------------------------+------+-------------------+--------------------------------------------------------------------------------------------------------+

IPv6

BGP dynamic routing supports peering via IPv6 and advertising IPv6
prefixes.

  • To enable peering via IPv6, create a BGP peer and use an IPv6
    address for peer_ip.
  • To enable advertising IPv6 prefixes, create an address scope with
    ip_version=6 and a BGP speaker with
    ip_version=6.

Note

DVR lacks support for routing directly to a fixed IPv6 address via
the floating IP agent gateway port and thus prevents the BGP speaker
from advertising /128 host routes.

High availability

BGP dynamic routing supports scheduling a BGP speaker to multiple
agents which effectively multiplies prefix advertisements to the same
peer. If an agent fails, the peer continues to receive advertisements
from one or more operational agents.

  1. Show available dynamic routing agents.

    $ openstack network agent list --agent-type bgp
    +--------------------------------------+---------------------------+------- --+-------------------+-------+-------+---------------------------+
    | ID                                   | Agent Type                | Host     | Availability Zone | Alive | State | Binary                    |
    +--------------------------------------+---------------------------+----------+-------------------+-------+-------+---------------------------+
    | 37729181-2224-48d8-89ef-16eca8e2f77e | BGP dynamic routing agent | bgp-ha1  | None              | :-)   | UP    | neutron-bgp-dragent       |
    | 1a2d33bb-9321-30a2-76ab-22eff3d2f56a | BGP dynamic routing agent | bgp-ha2  | None              | :-)   | UP    | neutron-bgp-dragent       |
    +--------------------------------------+---------------------------+----------+-------------------+-------+-------+---------------------------+
  2. Schedule BGP speaker to multiple agents.

    $ openstack bgp dragent add speaker 37729181-2224-48d8-89ef-16eca8e2f77e bgpspeaker
    Associated BGP speaker bgpspeaker to the Dynamic Routing agent.
    
    $ openstack bgp dragent add speaker 1a2d33bb-9321-30a2-76ab-22eff3d2f56a bgpspeaker
    Associated BGP speaker bgpspeaker to the Dynamic Routing agent.
    
    $ openstack bgp dragent list --bgp-speaker bgpspeaker
    +--------------------------------------+---------+-------+-------+
    | ID                                   | Host    | State | Alive |
    +--------------------------------------+---------+-------+-------+
    | 37729181-2224-48d8-89ef-16eca8e2f77e | bgp-ha1 | True  | :-)   |
    | 1a2d33bb-9321-30a2-76ab-22eff3d2f56a | bgp-ha2 | True  | :-)   |
    +--------------------------------------+---------+-------+-------+

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