bfd all-interfaces (OSPFv3)

Function

The bfd all-interfaces command enables BFD for OSPFv3 or configures bidirectional forwarding detection (BFD) specific parameters for OSPFv3.

The undo bfd all-interfaces command disables BFD for OSPFv3 or unconfigures BFD specific parameters for OSPFv3.

By default, BFD is not enabled or configured at OSPFv3 process level.

Format

bfd all-interfaces { enable | { min-transmit-interval min-transmit-value | min-receive-interval min-receive-value | detect-multiplier detect-multiplier-value } ^* }

undo bfd all-interfaces { enable | { min-transmit-interval [ min-transmit-value ] | min-receive-interval [ min-receive-value ] | detect-multiplier [ detect-multiplier-value ] } ^* }

Parameters

Parameter	Description	Value
enable	Indicates enable BFD for OSPFv3.	-
min-transmit-interval min-transmit-value	Indicates minimum transmit interval for BFD support in OSPFv3 on a given OSPFv3 process.	The value of min-transmit-value ranges from 3~1000, in milliseconds. By default, it is 10 milliseconds.
min-receive-interval min-receive-value	Indicates minimum receive interval for BFD support in OSPFv3 on a given OSPFv3 process.	The value of min-transmit-value ranges from 3~1000, in milliseconds. By default, it is 10 milliseconds.
detect-multiplier detect-multiplier-value	Indicates detect multiplier value for BFD support in OSPFv3 on a given OSPFv3 process.	The value of detect-multiplier-value ranges from 3 to 50. By default, it is 3.

Views

OSPFv3 view

Default Level

2: Configuration level

Usage Guidelines

Usage Scenario

You can run this command to enable BFD and configure BFD session parameters. Faults between adjacent devices, therefore, are quickly detected, OSPFv3 is instructed to recalculate routes, and OSPFv3 convergence speeds up. When the OSPFv3 neighbor relationship goes Down, the BFD session between OSPFv3 neighbors is dynamically deleted.
When you configure OSPFv3 IP FRR, the BFD status is associated with the link status of an interface (The link status of the interface goes Down if the BFD status goes Down) after the frr-binding command parameters are configured. So the lower layer fast responds to the link change, traffic is rapidly switched to the backup link, and faults are detected within a short time.

After OSPFv3 establishes a BFD session, the default parameter value is used. BFD session parameters can also be modified as required.

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.

Prerequisites

Before configuring BFD for OSPFv3, BFD must have been enabled globally using the bfd command.

After BFD in the OSPFv3 process is enabled using the bfd all-interfaces enable command, OSPFv3 establish BFD sessions only with neighbors whose status is Full.

Follow-up Procedure

Configure a BFD session on a specified interface.

If you need to configure BFD on specified interfaces, or global BFD for OSPFv3 is configured but some interface need to be quicker to find link faults, you can configure BFD on specified interfaces using the ospfv3 bfd command.
An interface is prevented from dynamically creating a BFD session.

If you do not want to enable BFD on specified interfaces, you can disable the interfaces from dynamically creating BFD sessions using the ospfv3 bfd block command.

Precautions

The bfd all-interfaces command and the ospfv3 bfd block command are mutually exclusive.

Example

# Enabling BFD on OSPFv3 process.

<sysname> system-view

[sysname] ospfv3 1

[sysname-ospfv3-1] bfd all-interfaces enable