OSPF Configuration Module

This configuration module configures OSPFv2 and OSPFv3 routing processes on most supported platforms (see supported features and platform support).

Supported Features

Supported OSPF features:

  • OSPFv2 and/or OSPFv3 (see platform support table and address families)

  • Multi-area deployment

  • Per-link cost and asymmetric costs

  • OSPF network type

  • Reference bandwidth

  • Unnumbered point-to-point interfaces

  • Passive interfaces

  • Static router ID

  • BFD (optionally with RFC9355 strict mode)

  • VRF OSPFv2 instances (on platforms with VRF support)

Missing features:

  • Stub and NSSA areas

  • Virtual links

  • Opaque LSA

  • Multi-area adjacencies

  • Demand circuits

  • A gazillion nerd knobs and IETF quirks

Need one of those? Create a plugin and contribute it.

Platform Support

The following table describes per-platform support of individual router-level OSPF features:

Operating system

Areas

Reference
bandwidth

OSPFv3

BFD

BFD
Strict-Mode

Arista EOS

✅

✅

✅

✅

❌

Aruba AOS-CX

✅

✅

✅

✅

❌

Cisco IOS

✅

✅

✅

✅

❌

Cisco IOS XRv

✅

✅

✅

❌

❌

Cisco IOS XE

✅

✅

✅

✅

❌

Cisco Nexus OS

✅

✅

✅

✅

❌

Cumulus Linux

✅

✅

✅

❌

❌

Cumulus Linux 5.0 (NVUE)

✅

✅

❌

❌

❌

Dell OS10 (❗)

✅

✅

✅

✅

❌

Fortinet FortiOS

❗

✅

❌

❌

❌

FRR 7.5.0

✅

✅

✅

❌

❌

Juniper vMX

✅

✅

✅

✅

❌

Juniper vPTX

✅

✅

✅

✅

❌

Juniper vSRX 3.0

✅

✅

✅

✅

❌

Mikrotik RouterOS 6

✅

❌

❌

✅

❌

Mikrotik RouterOS 7

✅

❌

✅

❌

❌

Nokia SR Linux

✅

✅

✅

✅

❌

Nokia SR OS

✅

✅

✅

✅

✅

VyOS

✅

✅

✅

✅

❌

Notes:

  • Mikrotik RouterOS and VyOS support BFD on OSPF only with the system default values for interval and multiplier.

  • Dell OS10 does not support OSPF on the so-called Virtual Network interface, which is the VLAN implementation model currently used in our templates.

The following table documents the interface-level OSPF features:

Operating system

Cost

Network
type

Unnumbered
interfaces

Passive
interfaces

Arista EOS

✅

✅

✅

✅

Aruba AOS-CX

✅

✅

❌

✅

Cisco IOS

✅

✅

❗

✅

Cisco IOS XE

✅

✅

✅

✅

Cisco IOS XRv

✅

✅

✅

✅

Cisco Nexus OS

✅

✅

✅

✅

Cumulus Linux

✅

✅

✅

✅

Cumulus Linux 5.0 (NVUE)

✅

✅

✅

✅

Dell OS10

✅

✅

❌

✅

Fortinet FortiOS

✅

❗

✅

✅

FRR 7.5.0

✅

✅

✅

❗

Juniper vMX

✅

✅

✅

✅

Juniper vPTX

✅

✅

✅

✅

Juniper vSRX 3.0

✅

✅

✅

✅

Mikrotik RouterOS 6

✅

✅

❌

✅

Mikrotik RouterOS 7

✅

✅

❌

✅

Nokia SR Linux

✅

✅

❌

✅

Nokia SR OS

✅

✅

✅

✅

VyOS

✅

✅

✅

✅

Notes:

  • Arista EOS, Cisco Nexus OS, SR Linux and Dell OS10 support point-to-point and broadcast network types. Other network types will not be configured.

  • SR OS supports point-to-point, broadcast and non-broadcast network types. Point-to-multipoint network type will not be configured.

  • FRR does not support passive interfaces with OSPFv3

Global Parameters

  • ospf.reference_bandwidth sets the OSPF auto-cost reference bandwidth (in Mbps) for all devices in the network.

  • ospf.bfd.strict enables RFC9355 BFD Strict-Mode (default: False)

Node Parameters

  • ospf.process – process ID (default: 1)

  • ospf.af – OSPF address families. Configures OSPFv2 and/or OSPFv3 on devices that support OSPFv3. Has no impact on other devices.

  • ospf.area – default OSPF area (default: 0.0.0.0). Used on links without explicit OSPF area, and on loopback interface.

  • ospf.reference_bandwidth – per-node OSPF auto-cost reference bandwidth (in Mbps).

  • ospf.bfd – enable BFD for OSPF (default: False)

  • ospf.router_id – set static router ID.

You can specify most node parameters as global values (top-level topology elements) or within individual nodes (see example for details).

VRF Parameters

  • You can specify default area for a VRF OSPF instance with VRF-level ospf.area parameter

  • You can change the router ID of a VRF OSPF instance with ospf.router_id parameter. Use this parameter when building back-to-back links between VRFs on the same node.

  • Set ospf.active to True to force a VRF to use OSPF even though there are no routers attached to the VRF interfaces.

  • To disable OSPF in a VRF set ospf to False (see also Disabling a Routing Protocol in VRF).

Example

We want to create a three-router multi-area OSPF network:

  • R1 is a backbone area router

  • R2 is ABR between backbone area and area 1

  • R3 is in intra-area router in area 1.

All devices run OSPF:

module: [ ospf ]

Default OSPF area is 0.0.0.0:

ospf:
  area: 0.0.0.0

R1 and R2 are in default OSPF area (no need to specify per-node area):

nodes:
  r1:
    device: iosv
  r2:
    device: eos

R3 is in area 1. Non-default OSPF area must be specified within node data:

nodes:
  r3:
    device: nxos
    ospf:
      area: 0.0.0.1

Link between R1 and R2 is in area 0. No need to specify per-link area:

links:
- r1:
  r2:

Link between R2 and R3 is in area 1. Specify OSPF area within link definition:

links:
- r2:
  r3:
  ospf:
    area: 0.0.0.1

Alternatively, you could specify the OSPF area just for R2 (as R3 is already in area 1):

links:
- r2:
    ospf:
      area: 0.0.0.1
  r3:

Interesting details:

  • The default value for interface OSPF area is the node OSPF area

  • The default value for node OSPF area is the global OSPF area (default value: 0.0.0.0).

  • Due to the propagation of default values, the OSPF area for R2-R3 link would be area 0 on R2 and area 1 on R3. The OSPF area thus needs to be specified within link definition, or within an individual node connected to a link.

Resulting Device Configurations

The above topology generates the following device configurations

R1 (Cisco IOS)

router ospf 1
!
interface Loopback0
 ip ospf 1 area 0.0.0.0
!
interface GigabitEthernet0/1
 ip ospf 1 area 0.0.0.0
 ip ospf network point-to-point

R2 (Arista EOS)

router ospf 1
!
interface Loopback0
 ip ospf area 0.0.0.0
!
interface Ethernet1
 ip ospf area 0.0.0.0
 ip ospf network point-to-point
!
interface Ethernet2
 ip ospf area 0.0.0.1
 ip ospf network point-to-point

R3 (Cisco Nexus-OS)

feature ospf
!
router ospf 1
!
interface loopback0
 ip router ospf 1 area 0.0.0.1
!
interface Ethernet1/1
 ip router ospf 1 area 0.0.0.1
 ip ospf network point-to-point

Complete network topology:

module: [ ospf ]

ospf:
  area: 0.0.0.0

nodes:
  r1:
    device: iosv
  r2:
    device: eos
  r3:
    device: nxos
    ospf:
      area: 0.0.0.1

links:
- r1:
  r2:

- r2:
  r3:
  ospf:
    area: 0.0.0.1