display bgp ipv6 bfd session

Function

The display bgp ipv6 bfd session command displays information about the BFD session set up by BGP4+.

Format

display bgp ipv6 bfd session { [ vpnv6 vpn-instance vpn-instance-name ] peer ipv6-address | all }

Parameters

Parameter	Description	Value
vpnv6	Displays the BFD session of VPNv6.	-
vpn-instance vpn-instance-name	Specifies the name of the VPN instance.	The value is a string of 1 to 31 case-sensitive characters and cannot contain spaces.
peer ipv6-address	Specifies the IPv6 address of the peer.	The value is a 32-bit hexadecimal number in X:X:X:X:X:X:X:X format.
all	Displays all BFD sessions set up by BGP.	-

Views

All views

Default Level

1: Monitoring level

Usage Guidelines

Usage Scenario

The BFD session set up by BGP4+ helps BGP4+ quickly discover faults between BGP4+ peers and inform BGP4+ to recalculate routes for packet forwarding.

Run the display bgp ipv6 bfd session command to display information about the BFD session set up by BGP4+ in the following situations:

Check whether the BFD session is successfully set up or view detailed information about the BFD session that is successfully configured.
Check whether the BFD session set up by BGP4+ is successfully deleted after running the undo peer bfd enable command.
Verify the configuration after running the undo peer bfd block command to prevent a peer from inheriting the BFD function of the peer group.
Verify the configuration after running the peer bfd command to set BFD parameters.

The information about the BFD session of a specified peer can be displayed by specifying different parameters.

Run the display bgp ipv6 bfd session vpnv6 vpn-instance vpn-instance-name peer ipv6-address command to display information about the BFD session of a specified peer in a VPN instance.
Run the display bgp ipv6 bfd session peer ipv6-address command to display information about the BFD session of a specified peer on the public network.
Run the display bgp ipv6 bfd session all command to display information about the BFD sessions of all BGP4+ peers.

Prerequisites

The BFD session has been set up using the peer bfd enable command. If the BFD session has not been set up by BGP4+, no information is displayed after running the display bgp ipv6 bfd session command.

Example

# Display all BFD sessions set up by BGP.

<sysname> display bgp ipv6 bfd session all
  Local_Address   : 2001:db8:11::11  Peer_Address    : 2001:db8:22::22
  Tx-interval(ms) : 1000             Rx-interval(ms) : 1000
  Multiplier      : 3                Interface       : Unknown
  LD/RD           : 1111/4444        Session-State   : Init
  Wtr-interval(m) : 0

VPN-Instance vrf1:
  Local_Address  : 2001:db8:1::2     Peer_Address   : 2001:db8:1::1
  Tx-interval(ms): 0                 Rx-interval(ms): 0
  Multiplier     : 0                 Interface      : Unknown
  LD/RD          : 8195/0            Session-State  : Init
  Wtr-interval(m): 0

**Table 1** Description of the **display bgp ipv6 bfd session** command output
Item	Description
Local_Address	Local address
Peer_Address	Peer address
Tx-interval (ms)	Interval for sending BFD packets, in milliseconds
Rx-interval (ms)	Interval for receiving BFD packets, in milliseconds
Multiplier	Local detection multiple
Interface	Interface on which the BFD session is set up NOTE: Information about the interface on which the BFD session is set up only when the directly connected interface is used to set up the EBGP neighbor relationship. In other cases, information about the interface is displayed as Unknown.
LD/RD	Local/remote discriminator
Session-State	BFD status Admin down: The BFD session is closed on the local end. BFD global disable: BFD is disabled globally. BFD session number exceed: The number of BFD sessions exceeds the maximum limit. Detect down: BFD detects a link status fault and interrupts the connection. Init: The BFD session is in the initialized state. Neighbor down: The peer end detects that the BFD session goes Down and informs the local end of the change, and the local end then sets the neighbor status to Down. Receive admin down: The BFD session is closed on the peer end (for example, the BFD session is disabled on the peer end). Up: The BFD session is set up.
Wtr-interval(m)	Interval for flap dampening, in minutes
VPN-Instance vrf1	VPN instance name