Configuring BFD for PIM over IPv6

Prerequisites

PIM must be enabled globally and on the specific interface that will support BFD.

Procedure

Enable BFD support with the command bfd.

For most deployments, the default values for the following features do not need to be changed. If your deployment requires different settings, change the default values with the indicated command:

BFD setting	Default value	Command to change it
Sets the BFD detection multiplier on an interface.	5	`bfd detect-multiplier`
Sets the minimum time interval between received BFD echo packets.	500 milliseconds	`bfd min-echo-receive-interval`
Sets the minimum time interval between transmitted BFD control packets on an interface.	3000 milliseconds	`bfd min-transmit-interval`

Configuring the timers to be too aggressive (for example, detect-multiplier of 1) can sometimes lead to BFD session flaps depending upon traffic conditions.

Switch to the interface on which you want to enable BFD with the command interface.
Enable BFD support with the command ip pim-sparse bfd.
Review BFD configuration settings with the commands show bfd.

Examples

This example shows how to configure PIM and enable BFD on interface 1/1/2.

switch# config
switch(config)# bfd
switch(config)# router pim6		
switch(config-pim)# enable
switch(config-pim)# exit
switch(config)# interface 1/1/2
switch(config-if)# no shutdown
switch(config-if)# ipv6 address 2130::1/64
switch(config-if)# ipv6 mld enable
switch(config-if)# ip pim-sparse enable
switch(config-if)# ip pim-sparse bfd
switch(config-if)# exit
switch(config)# exit
switch# show bfd
Admin status: enabled
Echo source IP: <none>
Statistics:
Total number of control packets transmitted: 8
Total number of control packets received: 8
Total number of control packets dropped: 0
Session Interface VRF       Source IP           Destination IP                Echo     State        Application
------- --------- --------- ------------------- ----------------------------- -------- ------------ ------------
1       1/1/2     default   N/A                 fe80::94f1:2821:2ef:6300      enabled  up           pimv6