bfd bind peer-ipv6 track-interface

Function

The bfd bind peer-ipv6 track-interface command creates a BFD for IPv6 session, binds related information to the BFD session, and displays the BFD session view.

By default, the binding between a BFD session for IPv6 and a peer IPv6 address is not created.

Format

bfd session-name bind peer-ipv6 peer-ipv6 [ vpn-instance vpn-name ] [ source-ipv6 source-ipv6 ] track-interface interface { interface-name | interface-type interface-number }

bfd session-name bind peer-ipv6 peer-ipv6 [ vpn-instance vpn-name ] [ source-ipv6 source-ipv6 ] track-interface controller { interface-name | interface-type interface-number }

Parameters

Parameter	Description	Value
session-name	Specifies the name of a BFD session for IPv6.	The value is a string of 1 to 64 case-insensitive characters, spaces not supported.
peer-ipv6	Specifies the peer IPv6 address bound to a BFD session for IPv6.	The address is a 32-digit hexadecimal number, in the format of X:X:X:X:X:X:X:X.
vpn-instance vpn-name	Specifies the name of a VPN instance bound to a BFD session for IPv6.	The value is a string of 1 to 31 case-sensitive characters, spaces not supported. In addition, the VPN instance name must not be _public_. When double quotation marks are used around the string, spaces are allowed in the string.
source-ipv6 source-ipv6	Specifies the source IPv6 address carried in a BFD packet. If no source IPv6 address is specified, a device uses a source IPv6 address in either of the following modes before sending BFD packets: During negotiation on BFD session for IPv6 parameters, the device searches for the IPv6 address of an outbound interface connected to the remote end in the local routing table as the source IPv6 address before sending BFD packets. During BFD for IPv6 detection, the device sets the source IPv6 address to a fixed value. This parameter is manually configured only when BFD works with Unicast Reverse Path Forwarding (URPF). This is because URPF checks the source IP address in received packets.	The address is a 32-digit hexadecimal number, in the format of X:X:X:X:X:X:X:X.
interface interface-type interface-number	Specifies track interface information of BFD session.	-
controller	Specify controller interface.	-

Views

System view

Default Level

2: Configuration level

Task Name and Operations

Task Name	Operations
bfd	write

Usage Guidelines

Usage Scenario

To rapidly detect IPv6 link faults on a network, create a BFD session for IPv6.

When creating the binding between a BFD session for IPv6 and a peer IPv6 address:

If only the peer IPv6 address is specified, BFD detects faults in a multi-hop link.
If both the peer IPv6 address and local interface are specified, BFD detects faults in a single-hop link. That is, BFD monitors a fixed route whose outbound interface is this interface and the next-hop address is the peer IPv6 address.
If both the peer IPv6 address and the VPN instance are specified, BFD detects faults in the multi-hop link for a specified VPN instance.
If the peer IPv6 address, the VPN instance, and the local interface are specified, BFD detects faults in the single-hop link for a specified VPN instance.

Prerequisites

BFD has been globally enabled using the bfd command in the system view.

Follow-up Procedure

After the binding is created, you must perform the following operations to create the BFD session for IPv6:

1.Run the discriminator command to create the local and remote discriminators for the BFD session for IPv6.

2.Run the commit command to commit the configuration.

After the binding is created, the following optional configurations can be performed in the BFD session for IPv6 view:

Run the description command to configure a description for the BFD session for IPv6.
Run the min-tx-interval command to set a desired minimum interval at which BFD for IPv6 packets are sent.
Run the min-rx-interval command to set a desired minimum interval at which BFD for IPv6 packets are received.
Run the detect-multiplier command to set a local detection multiplier of the BFD session for IPv6.
Run the process-pst command to enable BFD to modify the PST if BFD detects a fault.
Run the wtr command to set a WTR time for the BFD session for IPv6.

Precautions

If the IPv6 address of the outbound interface is changed after a BFD session for IPv6 has been created, either of the following situations occurs:

During negotiation, the source IPv6 address to be carried in BFD for IPv6 packets is updated.
During detection, the source IPv6 address carried in BFD for IPv6 packets is not updated.
Do not configure a changeable IP address (for example, an auto link-local address) as the peer IPv6 address.
A bidirectional BFD6 session monitors bidirectional links. Therefore, the bfd bind peer-ipv6 command must be configured on the two ends of the links.
You can run the undo bfd session-name command to delete a specified BFD session and its binding information.

Example

# Create a static BFD for IPv6 session with the name atob and check the single-hop link from the local interface GE 0/1/0 to the peer IP address 2001:db8::1.

<HUAWEI> system-view
[~HUAWEI] bfd
[*HUAWEI-bfd] quit
[*HUAWEI] interface GigabitEthernet 0/1/0
[*HUAWEI-GigabitEthernet0/1/0] ipv6 enable
[*HUAWEI-GigabitEthernet0/1/0] ipv6 address 2001:db8::3 64
[*HUAWEI-GigabitEthernet0/1/0] quit
[*HUAWEI] bfd atob bind peer-ipv6 2001:db8::1 track-interface interface GigabitEthernet 0/1/0