Common Routing Protocol Parameters

The following parameters are supported by most routing protocol modules:

Router ID

Router ID is configured with router_id node parameter (applies to all routing protocols) or with protocol.router_id node parameter (applies to the selected routing protocol). Router ID can be configured as an IPv4 address or as an integer.

Default router_id is taken from the IPv4 address of the loopback interface or from the router_id address pool if there’s no usable IPv4 address on the loopback interface.

Example:

modules: [ ospf, bgp ]

nodes:
  r1:
    router_id: 10.0.0.1
  r2:
    ospf.router_id: 10.0.0.2
    bgp.router_id: 10.0.1.2
  r3:
  • Router ID for R1 is configured for the whole device and used for OSPFv2/OSPFv3 and BGP

  • OSPFv2/OSPFv3 router ID for R2 is 10.0.0.2. BGP router ID for R2 is 10.0.1.2

  • Node ID for R3 is 3 (the third node in the nodes dictionary). Router ID for R3 is taken from the loopback interface (10.0.0.3 unless you changed the loopback address pool) or from the router_id address pool (10.0.0.3).

Address Families

Configuration modules for all IGP routing protocols that support multiple address families (IS-IS, EIGRP) or multiple protocol instances (OSPFv2, OSPFv3) support protocol.af global- or node-level module parameter. The af parameter can be a list- or a dictionary of address families.

The default value of the af parameter is set based on address families configured on loopback- or physical interfaces – an address family is enabled within an IGP configuration on a device if at least one interface on that device has an IP address from that address family.

Example:

module: [ isis,ospf ]
isis.af.ipv6: True

nodes:
  r1:
    isis.af: [ ipv4, ipv6 ]
  r2:
    isis.af.ipv4: True
  r3:
    isis.af:
      ipv4: True
      ipv6: False
  r4:
    isis.af:
  r5:
  • IS-IS address families are enabled based on configured isis.af parameters

  • ospf.af parameter is not set – OSPFv2 or OSPFv3 are enabled based on address families used on individual nodes

The following IS-IS address families are configured on individual routers:

  • R1: IPv4 and IPv6. The configured list of addresses families overrides the topology defaults

  • R2: IPv4 and IPv6. Node- and global parameters are dictionaries and can be merged.

  • R3: IPv4 only. The isis.af parameter is fully specified within the node data, and explicitly disables IPv6 AF.

  • R4: The isis.af parameter is set to an empty value, and is therefore calculated from the address families.

  • R5: IPv6 only (global default)

Passive Interfaces

An interface is configured as a passive interface (when supported by the routing protocol implementation) if:

  • The link type is set to stub, or

  • The link role is set to stub or passive, or

  • protocol.passive parameter is set to True on a link or interface.

Example:

module: [ ospf ]

nodes: [ r1, r2 ]

links:
- r1:
  r2:
- r1:
- r1:
  r2:
  role: stub
- r1:
  r2:
    ospf.passive: True
- r1:
  r2:
    ospf.passive: False
  role: stub
  • The first link is a transit link

  • The second link is a stub link (single node attached to the link) ⇨ passive interface on R1

  • The third link has stub role ⇨ passive interfaces on R1 and R2

  • The fourth link is a transit link, but the ospf.passive value is set on R2 interface ⇨ regular interface on R1, passive interface on R2

  • The last link has stub role, but the ospf.passive value is set to False on R2 interface ⇨ passive interface on R1, regular interface on R2.

External Interfaces

Links with role: external are not included in the IGP routing processes. The external role can be set with a link parameter or by the BGP module.

BGP module sets link role specified in defaults.bgp.ebgp_role on links connecting devices with different AS numbers. The system default value of that parameter is external, making inter-AS links excluded from the IGP processes.

If you want to include external subnets into your IGP (and disable BGP next_hop_self processing), set defaults.bgp.ebgp_role to passive.