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Cisco ASA 5500 Series Configuration Guide using ASDM
Chapter29 Configuring Multicast Routing
Customizing Multicast Routing
Step5 Click the Use this RP for All Multicast Groups radio button to use the specified RP for all multicast
groups on the interface, or the Use this RP for the Multicast Groups as specified below radio button
to designate the multicast groups to use with the specified RP.
For more information about multicast groups, see the “Configuring a Multicast Group” section on
page 29-14.
Step6 Click OK.
Configuring the Designated Router Priority
The DR is responsible for sending PIM register, join, and prune messages to the RP. When there is more
than one multicast router on a network segment, selecting the DR is based on the DR priority. If multiple
devices have the same DR priority, then the device with the highest IP address becomes the DR.
By default, the ASA has a DR priority of 1. To change this value, perform the following steps:
Step1 In the main ASDM window, choose Configuration > Device Setup > Routing > Multicast > PIM >
Protocol.
Step2 Choose the interface that you want to enable for PIM from the table on the Protocol pane, and click Edit.
The Edit PIM Protocol dialog box appears.
Step3 In the DR Priority field, type the value for the designated router priority for the selected interface. The
router with the highest DR priority on the subnet becomes the designated router. Valid values range from
0 to 4294967294. The default DR priority is 1. Setting this value to 0 makes the ASA interface ineligible
to become the default router.
Step4 Click OK.
Configuring and Filtering PIM Register Messages
When the ASA is acting as an RP, you can restrict specific multicast sources from registering with it to
prevent unauthorized sources from registering with the RP. The Request Filter pane lets you define the
multicast sources from which the ASA will accept PIM register messages.
To filter PIM register messages, perform the following steps:
Step1 In the main ASDM window, choose Configuration > Device Setup > Routing > Multicast > PIM >
Request Filter.
Step2 Click Add.
The Request Filter Entry dialog box lets you define the multicast sources that are allowed to register with
the ASA when the ASA acts as an RP. You create the filter rules based on the source IP address and the
destination multicast address.
Step3 From the Action drop-down list, choose Permit to create a rule that allows the specified source of the
specified multicast traffic to register with the ASA, or choose Deny to create a rule that prevents the
specified source of the specified multicast traffic from registering with the ASA.
Step4 In the Source IP Address field, type the IP address for the source of the register message.