Using a Scope Policy for Multicast Scoping

To configure multicast scoping with a scope policy, include the scope-policy statement and specify one or more policy names for the scope:

For a list of the hierarchy levels at which you can include this statement, see the statement summary section for this statement.

Each referenced policy must be correctly configured at the [edit policy-options] hierarchy level, specifying the set of routing device interfaces on which to configure scoping, and defining the scope's address range as a series of route filters. Only the interface, route-filter, and prefix-list match conditions are supported for multicast scope policies. All other configured match conditions are ignored. The only actions supported are accept, reject, and the policy flow actions next-term and next-policy. The reject action means that joins and multicast forwarding are suppressed in both directions on the configured interfaces. The accept action allows joins and multicast forwarding in both directions on the interface. By default, scope policies apply to all interfaces. The default action is accept.

For more information about configuring route filters and policies, see the Junos Policy Framework Configuration Guide.

Note: Multicast scoping configured with a scope policy differs in several ways from scoping configured with a named scope (which uses the scope statement): You cannot apply a scope policy to a specific routing instance, because all scope policies apply to all routing instances. In contrast, a named scope does apply individually to a specific routing instance. In contrast to scoping with a named scope, scoping with a scope policy does not automatically add the local scope at scope boundaries. You must explicitly configure the local scope boundaries. The local scope limits the use of the multicast group 239.255.0.0/16 to an attached LAN. When you configure multicast scoping with a scope policy, the show multicast scope operational mode command displays only the name of the scope policy. When you configure scoping with a named scope, the command displays the names of the defined scopes, prefixes, and interfaces. For information about named scopes and the scope statement, see Creating a Named Scope for Multicast Scoping.