Configuring BFD-OSPF Interworking

You can configure BFD features on the link running OSPF in the scenarios where data transmission poses high requirements on timeliness and OSPF convergence needs to be sped up upon link status changes.

Prerequisites

Before you configure BFD-OSPF interworking, complete the following tasks on devices at both ends:

Setting the IP addresses of interfaces to ensure reachable adjacent nodes.
Configuring basic OSPF functions to enable neighbor relationship in Full state. For details, see Configuring OSPF Using the CLI.
Configure global BFD functions, including enabling BFD and adjusting global parameters. For details, see Configuring Global BFD Functions.

Context

Note that BFD-OSPF interworking needs to be configured on devices at both ends.

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

Enable BFD in the OSPF process.

To enable BFD on all interfaces in the OSPF 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 OSPF 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 OSPF process, you can enable BFD on the specified interface.

Procedure

Access the system view.
```
system-view
```
Select one of the following configuration modes as required.
- Enable BFD in the OSPF process.
  1. Access the OSPF view.
```
ospf [ process-id ]
```
  2. Enable BFD in the OSPF process and create BFD sessions.
```
bfd all-interfaces enable
```
    After BFD is enabled in the OSPF process, BFD sessions are created on all interfaces whose neighbor status is Full in the process.
  3. (Optional) Configure BFD session parameters.
```
bfd all-interfaces { detect-multiplier multiplier-value | min-rx-interval receive-interval | min-tx-interval transmit-interval } ^*
```
    - The default value of the local detection multiple is 3.
    - The default value of minimum receiving interval is 1000 ms, and the default value of minimum sending interval is 1000 ms.
    - If no BFD packet is received from the peer end at the value of receive-interval × multiplier-value (the value of receive-interval is negotiated based on the local min-rx-interval and remote min-tx-interval), BFD mistakenly considers that the neighbor becomes Down.
    - If only parameters for the BFD session are specified, no BFD session is created.
  4. Return to the system view.
```
quit
```
  5. Access the interface view.
```
interface interface-type interface-number
```
  6. (Optional) Disable the function of dynamically creating BFD sessions on the interface.
```
ospf bfd block
```
    After BFD is enabled on all interfaces in the OSPF process, you can run this command on certain interfaces to reduce monitored links. This improves performance.
- Enable BFD on the interface.
  1. Access the interface view.
```
interface interface-type interface-number
```
  2. Enable BFD on the OSPF-enabled interface.
```
ospf bfd enable
```
  3. (Optional) Configure BFD session parameters.
```
ospf bfd { detect-multiplier multiplier-value | min-rx-interval receive-interval | min-tx-interval transmit-interval } ^*
```
    - The default value of the local detection multiple is 3.
    - The default value of minimum receiving interval is 1000 ms, and the default value of minimum sending interval is 1000 ms.
    - Because the priority of BFD on the interface is higher than that of BFD in the OSPF process, the parameters of the BFD session on the interface enjoy higher priorities than those of the BFD session in the OSPF process.