Configuring OSPFv3-BFD Interworking

Configuring BFD for OSPFv3 helps the system to rapidly detect the link status and speeds up OSPFv3 convergence in the case of a link failure.

Prerequisites

Before configuring BFD for OSPFv3, complete the following tasks:

Assigning an IP address to each interface to ensure reachability between neighboring nodes at the network layer
Configuring basic OSPFv3 functions. For details, see Configuring OSPFv3 Using the CLI.
Configure global BFD functions, including enabling BFD and adjusting global parameters. For details, see Configuring Global BFD Functions.

Context

After BFD for OSPFv3 is configured, when detecting a link fault, BFD rapidly notifies the routers on both ends of the link of the fault, triggering rapid OSPFv3 convergence. When the OSPFv3 neighbor relationship goes Down, the BFD session will be dynamically deleted.

You can select one of the following modes to configure BFD-OSPFv3 interworking:

Enable BFD in the OSPFv3 process.

To enable BFD on all interfaces in the OSPFv3 process, enable BFD on all interfaces of devices at both ends of the link where the BFD session is to be established.
Enable BFD on the interface.

The priority of BFD on the interface is higher than that of BFD in the OSPFv3 process.

To enable BFD on certain interfaces or enable certain interfaces to rapidly identify link faults in the case that BFD is enabled in the OSPFv3 process, you can enable BFD on the specified interface.

Procedure

Configuring BFD for OSPFv3 in a Specified Process
1. Run:
  ospfv3 [ process-id ]
  
  The OSPF process view is displayed.
2. Run:
  bfd all-interfaces enable
  
  BFD for OSPFv3 is enabled to establish a BFD session.
  
  By default, BFD is disabled at OSPFv3 process level.
3. Run:
  bfd all-interfaces { min-transmit-interval min-transmit-value | min-receive-interval min-receive-value | detect-multiplier detect-multiplier-value } ^*
  
  OSPFv3 BFD parameters are configured.
  
  You can skip this step. The default interval at which BFD packets are transmitted and the default detection multiplier are recommended.
  
  The parameters are configured based on the network status and network reliability requirements. A short interval at which BFD packets are transmitted can be configured for a link that has a higher requirement for reliability. A long interval at which BFD packets are transmitted can be configured for a link that has a lower requirement for reliability.
  - Actual interval at which BFD packets are transmitted on the local devices = Max { configured interval min-transmit-value at which BFD packets are transmitted, configured interval min-receive-value at which BFD packets are received on the peer device }
  - Actual interval at which BFD packets are received on the local devices = Max { configured interval min-transmit-value at which BFD packets are transmitted on the peer device, configured interval min-receive-value at which BFD packets are received on the local device }
  - Actual time for detecting BFD packets = Actual interval at which BFD packets are received on the local device x Configured detection multiplier detect-multiplier-value
  For example:
  - On the local device, the configured interval at which BFD packets are transmitted is 200 ms; the interval at which BFD packets are received is set to 300 ms; the detection multiplier is 4.
  - On the peer device, the configured interval at which BFD packets are transmitted is 100 ms; the interval at which BFD packets are received is 600 ms; the detection multiplier is 5.
  Then:
  - On the local device, the actual interval at which BFD packets are transmitted is 600 ms calculated by using the formula max {200 ms, 600 ms}; the interval at which BFD packets are received is 300 ms calculated by using the formula max {100 ms, 300 ms}; the detection period is 1500 ms calculated by multiplying 300 ms by 5.
  - On the peer device, the actual interval at which BFD packets are transmitted is 300 ms calculated by using the formula max {100 ms, 300 ms}, the actual interval at which BFD packets are received is 600 ms calculated by using the formula max {200 ms, 600 ms}, and the detection period is 2400 ms calculated by multiplying 600 ms by 4.
Configuring BFD for OSPFv3 on a Specified Interface
1. Run:
  interface interface-type interface-number
  
  OSPFv3 BFD is enabled on the interface.
  
  By default, OSPFv3 BFD is disabled at interface level.
2. Run:
  ospfv3 bfd enable [ instance instance-id ]
  
  OSPFv3 BFD is enabled on the interface.
  
  The priority of BFD for OSPFv3 configured on an interface is higher than that of BFD for OSPFv3 configured for a process.
3. Run:
  ospfv3 bfd { min-transmit-interval min-transmit-value | min-receive-interval min-receive-value | detect-multiplier detect-multiplier-value } ^* [ instance instance-id ]
  
  OSPFv3 BFD parameters are configured at interface level.