display bgp bfd session

Function

The display bgp bfd session command displays information about the BFD session set up by BGP.

Format

display bgp bfd session { [ vpnv4 vpn-instance vpn-instance-name ] peer ipv4-address | all }

Parameters

Parameter	Description	Value
vpnv4	Displays the BFD session of VPNv4.	-
vpn-instance vpn-instance-name	Displays the BFD session of a specified VPN instance.	The value is a string of 1 to 31 case-sensitive characters, spaces not supported. When double quotation marks are used around the string, spaces are allowed in the string.
peer ipv4-address	Displays the BFD session of a specified BGP peer.	It is in dotted decimal notation.
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 BGP helps BGP quickly discover faults between BGP peers and inform BGP to recalculate routes for packet forwarding.

Run the display bgp bfd session command to display information about the BFD session set up by BGP 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 BGP 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 BGP peer can be displayed by specifying different parameters.

Run the display bgp bfd session vpnv4 vpn-instance vpn-instance-name peer ipv4-address command to display information about the BFD session of a specified BGP peer in a specified VRF.
Run the display bgp bfd session peer ipv4-address command to display information about the BFD session of a specified BGP peer on the public network.
Run the display bgp bfd session all command to display information about the BFD sessions of all BGP 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 BGP, no information is displayed after running the display bgp bfd session command.

Example

# Display all BFD sessions set up by BGP.

<sysname> display bgp bfd session all

  Local_Address      Peer_Address       LD/RD       Interface
  2.2.2.2            1.1.1.1            8192/8192   Unknown
  Tx-interval(ms)    Rx-interval(ms)    Multiplier  Session-State
  1000               1000               3           Up
  Wtr-interval(m)
  0

  Local_Address      Peer_Address       LD/RD       Interface
  10.1.1.1           10.1.1.2           8193/0      Unknown
  Tx-interval(ms)    Rx-interval(ms)    Multiplier  Session-State
  0                  0                  0           Receive admin down
  Wtr-interval(m)
  0

VPN-Instance vrf1:
  Local_Address      Peer_Address       LD/RD       Interface
  10.1.1.2           10.1.1.1           8192/8192   GigabitEthernet0/0/0
  Tx-interval(ms)    Rx-interval(ms)    Multiplier  Session-State
  1000               1000               3           Up
  Wtr-interval(m)
  0

**Table 1** Description of the **display bgp bfd session** command output
Item	Description
Local_Address	Local address
Peer_Address	Peer address
LD/RD	Local/remote discriminator
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.
Tx-interval (ms)	Interval for sending BFD packets, in milliseconds
Rx-interval (ms)	Interval for receiving BFD packets, in milliseconds
Multiplier	Local detection multiple
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