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Cisco ASA Series CLI Configuration Guide
Chapter 1 Configuring Multicast Routing
Customizing Multicast Routing
Configuring a Static Multicast Route
Configuring static multicast routes lets you separate multicast traffic from unicast traffic. For example,
when a path between a source and destination does not support multicast routing, the solution is to
configure two multicast devices with a GRE tunnel between them and to send the multicast packets over
the tunnel.
When using PIM, the ASA expects to receive packets on the same interface where it sends unicast
packets back to the source. In some cases, such as bypassing a route that does not support multicast
routing, you may want unicast packets to take one path and multicast packets to take another.
Static multicast routes are not advertised or redistributed.
To configure a static multicast route or a static multicast route for a stub area, enter one of the following
commands:
Configuring IGMP Features
IP hosts use the Internet Group Management Protocol (IGMP) to report their group memberships to
directly connected multicast routers.
IGMP is used to dynamically register individual hosts in a multicast group on a particular LAN. Hosts
identify group memberships by sending IGMP messages to their local multicast router. Under IGMP,
routers listen to IGMP messages and periodically send out queries to discover which groups are active
or inactive on a particular subnet.
Command Purpose
igmp forward interface if_name
Example:
hostname(config-if)# igmp forward
interface interface1
Configures stub multicast routing and forwards IGMP messages.
Command Purpose
mroute src_ip src_mask {input_if_name |
rpf_neighbor} [distance]
Example:
hostname(config)# mroute src_ip src_mask
{input_if_name | rpf_neighbor} [distance]
Configures a static multicast route.
mroute src_ip src_mask input_if_name
[dense output_if_name] [distance]
Example:
hostname(config)# mroute src_ip src_mask
input_if_name [dense output_if_name]
[distance]
Configures a static multicast route for a stub area.
The dense output_if_name keyword and argument pair is only supported
for stub multicast routing.