Configuring PIM Bootstrap Properties for IPv4

For correct operation, every multicast router within a PIM domain must be able to map a particular multicast group address to the same Rendezvous Point (RP). The bootstrap router mechanism is one way that a multicast router can learn the set of group-to-RP mappings. Bootstrap routers are supported in IPv4 and IPv6.

Note: For legacy configuration purposes, this guide contains two sections that describe configuration of bootstrap routers: One section for both IPv4 and IPv6 and this section, which is for IPv4 only. The method described in Configuring PIM Bootstrap Properties for IPv4 or IPv6 is recommended. A commit error occurs if the same IPv4 bootstrap statements are included in both the IPv4-only and the IPv4-and-IPv6 sections of the hierarchy. The error message is “duplicate IPv4 bootstrap configuration.”

To determine which routing device is the RP, all routing devices within a PIM domain collect bootstrap messages. A PIM domain is a contiguous set of routing devices that implement PIM; all are configured to operate within a common boundary. The domain's bootstrap router originates bootstrap messages, which are sent hop by hop within the domain. The routing devices use bootstrap messages to distribute RP information dynamically and to elect a bootstrap router when necessary.

You can configure bootstrap properties globally or for a routing instance. This example shows the global configuration.

To configure the bootstrap router properties:

Configure the bootstrap priority.
By default, each routing device has a bootstrap priority of 0, which means the routing device can never be the bootstrap router. A priority of 0 disables the function for IPv4 and does not cause the routing device to send BSR packets with a 0 in the priority field. The routing device with the highest priority value is elected to be the bootstrap router. In the case of a tie, the routing device with the highest IP address is elected to be the bootstrap router. A simple bootstrap configuration simply assigns a bootstrap priority value to a routing device.
user@host# edit protocols pim rpuser@host# set bootstrap-priority 3
(Optional) Create import and export policies to control the flow of IPv4 bootstrap messages to and from the RP, and apply them to PIM. Import and export policies are useful when some of the routers in your PIM domain have interfaces that connect to other PIM domains. Configuring a policy prevents bootstrap messages from crossing domain boundaries. The bootstrap-import statement prevents messages from being imported into the RP. The bootstrap-export statement prevents messages from being exported from the RP.
[edit protocols pim rp]user@host# set bootstrap-import pim-bootstrap-importuser@host# set bootstrap-export pim-bootstrap-exportuser@host# exit
Configure the policies.
user@host# edit policy-options policy-statement pim-bootstrap-import[edit policy-options policy-statement pim-bootstrap-import]user@host# set from interface se-0/0/0user@host# set then rejectuser@host# exituser@host# edit policy-options policy-statement pim-bootstrap-exportuser@host# set from interface se-0/0/0user@host# set then rejectuser@host# exit
Monitor the operation of PIM bootstrap routers by running the show pim bootstrap command.

Configuring PIM Bootstrap Properties for IPv4

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