neighbor bfd

Enables Bidirectional Forwarding Detection (BFD) sessions for specified Border Gateway Protocol (BGP) neighbors or peer groups.

Syntax

neighbor { ip-address | ipv6-address | peer-group-name } bfd [ holdover-interval time | interval transmit-time min-rx receive-time multiplier number ]

no neighbor { ip-address | ipv6-address | peer-group-name } bfd [ holdover-interval time | interval transmit-time min-rx receive-time multiplier number ]

Command Default

BFD sessions are not enabled on specific BGP neighbors or peer groups.

Parameters

ip-address: Specifies the IP address of the neighbor.
ipv6-address: Specifies the IPv6 address of the neighbor.
peer-group-name: Specifies a peer group.
holdover-interval time: Specifies the holdover interval, in seconds, for which BFD session down notifications are delayed before notification that a BFD session is down. Valid values range from 1 through 30.
interval transmit-time: Specifies the interval, in milliseconds, a device waits to send a control packet to BFD peers. Valid values range from 50 through 30000.
min-rx receive-time: Specifies the interval, in milliseconds, a device waits to receive a control packet from BFD peers. Valid values range from 50 through 30000.
multiplier number: Specifies the number of consecutive BFD control packets that must be missed from a BFD peer before BFD determines that the connection to that peer is not operational. Valid values range from 3 through 50.

Modes

BGP configuration mode

BGP address-family IPv4 unicast VRF configuration mode

BGP address-family IPv6 unicast VRF configuration mode

Usage Guidelines

Before using the holdover-interval, interval, min-rx, and multiplier parameters, you must first enable BFD using the neighbor {ip-address | ipv6-address | peer-group-name } bfd command.

For single-hop BFD sessions, BFD considers the interval values that are configured on the interface, but not the nondefault values that are configured with this global command.

The no form of the command removes the BFD for BGP configuration for BGP neighbors or peer groups.

Examples

The following example configures BFD for a specified peer group and sets the BFD holdover interval to 18.

device# configure terminal
device(config)# router bgp
device(config-bgp-router)# neighbor pg1 bfd 
device(config-bgp-router)# neighbor pg1 bfd holdover-interval 18

The following example configures BFD for a BGP neighbor with the IP address 10.10.1.1 and sets the BFD session timer values.

device# configure terminal
device(config)# router bgp
device(config-bgp-router)# neighbor 10.10.1.1 bfd
device(config-bgp-router)# neighbor 10.10.1.1 bfd interval 120 min-rx 150 multiplier 8