Cisco Systems 78-11741-02 Limiting the Rate of PIM Register Messages, Enabling Proxy Registering

Configuring IP Multicast Routing

Advanced PIM Features Configuration Task List

Limiting the Rate of PIM Register Messages

To set a limit on the maximum number of PIM-SM register messages sent per second for each (S, G) routing entry, use the following global configuration command on the DR:

Command	Purpose
Router(config)# ip pim register-rate-limit rate	Sets a limit on the maximum number of PIM-SM register
	messages sent per second for each (S, G) routing entry.

Dataless register messages are sent at a rate of 1 message per second. Continuous high rates of register messages may occur if a DR is registering bursty sources (sources with high data rates) and if the RP is not running PIM Version 2.

By default, this command is not configured and register messages are sent without limiting their rate. Enabling this command will limit the load on the DR and RP at the expense of dropping those register messages that exceed the set limit. Receivers may experience data packet loss within the first second in which packets are sent from bursty sources.

Configuring the IP Source Address of Register Messages

Register messages are unicast messages sent by the DR to the RP router when a multicast packet needs to be sent on a rendezvous point tree (RPT). By default, the IP source address of the register message is set to the address of the outgoing interface of the DR leading toward the RP. To configure the IP source address of a register message to an interface address other than the outgoing interface address of the DR leading toward the RP, use the following command in global configuration mode:

Command	Purpose
Router(config)# ip pim register-source type number	Configures the IP source address of a register message.

Enabling Proxy Registering

In a PIM-SM domain, receivers know about sources because the DR connected to the source registers the source with the RP. By default, a DR will only register sources that are connected to it or that are forwarded to the DR from a DVMRP router.

For a router in a PIM-SM domain configured to operate in sparse mode or sparse-dense mode, the ip pim dense-modeproxy-registerinterface configuration command must be configured on the interface leading toward the bordering dense mode region. This configuration will enable the router to register traffic from the dense mode region with the RP in the sparse mode domain.

To enable proxy registering, use the following command in interface configuration mode:

Command	Purpose
Router(config-if)# ip pim dense-mode	Enables proxy registering on the interface of a DR (leading
[proxy-register {list access-listroute-map	toward the bordering dense mode region) for multicast traffic
map-name}]	from sources not connected to the DR.

Cisco IOS IP Configuration Guide

IPC-427