bfd bind peer-ipv6

Function

The bfd bind peer-ipv6 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 ] [ interface { interface-name | interface-type interface-number } ] [ source-ipv6 source-ipv6 ]

Parameters

Parameter	Description	Value
session-name	Specifies the name of a BFD session for IPv6.	The value is a string of 1 to 64 characters, spaces not supported. When quotation marks are used around the string, spaces are allowed in the string. When the name of a BFD session is configured, the uppercase and lowercase letters in the name must be the same as what you enter. BFD session names are case-insensitive. For example, ABC and abc are regarded as the same BFD session. If you have configured ABC as the name of a BFD session, the ABC BFD session view is directly displayed when you configure abc.
peer-ipv6	Specifies the peer IPv6 address bound to a BFD session for IPv6.	The value is in 32-digit hexadecimal notation.
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.
interface interface-type interface-number	Specifies the type and number of a Layer 3 interface to which a BFD session for IPv6 is bound.	-
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.	The value is in 32-digit hexadecimal notation.

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.
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.
If a source address is specified, the source-ipv6 parameter is used to ensure that BFD packets are not discarded after URPF is enabled. You must specify the correct source IPv6 address. This is because the system only checks whether the parameter is a valid source IPv6 address (for example, the address cannot be a multicast or broadcast address) and does not check the correctness.
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.

Configuration Impact

You can run the bfd bind peer-ipv6 command to create the binding between a static BFD session for IPv6 and a peer IPv6 address.

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 to the peer IPv6 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::2 64
[*HUAWEI-GigabitEthernet0/1/0] quit
[*HUAWEI] bfd atob bind peer-ipv6 2001:db8::1 interface GigabitEthernet 0/1/0

# Create a BFD session for IPv6 named s1 so that BFD for IPv6 can detect faults in the multi-hop link to the peer IPv6 address 2001:db8::1.

<HUAWEI> system-view
[~HUAWEI] bfd
[*HUAWEI-bfd] quit
[*HUAWEI] bfd s1 bind peer-ipv6 2001:db8::1