Configuring a BSR

Configure the router to advertise itself as the Candidate Bootstrap Router (Candidate-BSR) for the PIM-SM domain.

Prerequisites

You must be in the PIM configuration context, as indicated by the switch(config-pim)# prompt for IPv4 or the switch(config-pim6)# prompt for IPv6.

PIM-SM must be enabled on the interface used as the source IP interface.

Procedure

Configure a Candidate-BSR using the following command.
bsr-candidate source-ip-interface <INTERFACE-NAME>

For example, the following command configures a Candidate-BSR using interface 1/1/4 as the source for the router IP address. This command can also be applied to an L3 VLAN or L3 LAG.

For IPv4 configurations:
```
switch(config)# router pim
switch(config-pim)# bsr-candidate source-ip-interface 1/1/4
```
For IPv6 configurations:
```
switch(config)# router pim6
switch(config-pim6)# bsr-candidate source-ip-interface 1/1/4
```
Candidate-BSR can be enabled on a loopback interface as well. For a Candidate-BSR, you can configure various options as shown in the following steps.
Configure the bootstrap message (BSM) interval for sending periodic RP-Set messages using the following command.
bsr-candidate bsm-interval <INTERVAL-VALUE>

For example, the following command configures a bootstrap message interval of 150 seconds:

For IPv4 configurations:
```
switch(config)# router pim
switch(config-pim)# bsr-candidate bsm-interval 150
```
For IPv6 configurations:
```
switch(config)# router pim6
switch(config-pim6)# bsr-candidate bsm-interval 150
```
Set the priority to apply to the router when a BSR election process occurs in the PIM-SM domain using the following command.
bsr-candidate priority <PRIORITY-VALUE>

For example, the following command configures the priority as 250:

For IPv4 configurations:
```
switch(config)# router pim
switch(config-pim)# bsr-candidate priority 250
```
For IPv6 configurations:
```
switch(config)# router pim6
switch(config-pim6)# bsr-candidate priority 250
```
Configure the length (in bits) of the hash-mask using the following command. Used to control the distribution of multicast groups among the C-RP in a domain where there is overlapping coverage of the groups among the RPs.
bsr-candidate hash-mask-length <LENGTH-VALUE>

For example, the following command configures the hash-mask length to 4:

For IPv4 configurations:
```
switch(config)# router pim
switch(config-pim)# bsr-candidate hash-mask-length 4
```
For IPv6 configurations:
```
switch(config)# router pim6
switch(config-pim6)# bsr-candidate hash-mask-length 4
```