BGP Domains Plugin

The bgp.domain plugin allows you to create multiple independent copies of the same autonomous system, for example, when testing MPLS/VPN topologies in which all customer sites use the same AS number.

Using the default netlab IBGP session establishment rules, you’d get an IBGP session between the loopback interfaces of CE1 and CE2, resulting in “interesting” BGP tables and (potentially) recursive routing.

With the bgp.domain plugin, you can specify a BGP domain for each router, effectively splitting routers using the same BGP AS number into smaller sets. This is how you would describe the above topology using the bgp.domain plugin:

module: [ bgp, ospf ]
plugin: [ bgp.domain ]
defaults.device: cumulus

nodes:
  ce1:
    bgp.as: 65000
    bgp.domain: site_a
  ce2:
    bgp.as: 65000
    bgp.domain: site_b
  pe1:
    id: 10
    bgp.as: 65100
  pe2:
    id: 11
    bgp.as: 65100

links: [ ce1-pe1, pe1-pe2, pe2-ce2 ]

Supported Platforms

The plugin modifies the list of IBGP sessions generated by the BGP Configuration Module and works with any platform supported by that module.

New Attributes

The plugin defines a new node attribute:

• bgp.domain (string) – the domain of a BGP router (default: default)