Cisco 500 Series, Configuration Manual

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Cisco Security Appliance Command Line Configuration Guide
OL-12172-03
Chapter 11 Configuring Multicast Routing
Configuring Stub Multicast Routing
Note The igmp query-timeout and igmp query-interval commands require IGMP Version 2.
Changing the Query Response Time
By default, the maximum query response time advertised in IGMP queries is 10 seconds. If the security
appliance does not receive a response to a host query within this amount of time, it deletes the group.
To change the maximum query response time, enter the following command:
hostname(config-if)# igmp query-max-response-time seconds
Changing the IGMP Version
By default, the security appliance runs IGMP Version 2, which enables several additional features such
as the
igmp query-timeout and igmp query-interval commands.
All multicast routers on a subnet must support the same version of IGMP. The security appliance does
not automatically detect version 1 routers and switch to version 1. However, a mix of IGMP Version 1
and 2 hosts on the subnet works; the security appliance running IGMP Version 2 works correctly when
IGMP Version 1 hosts are present.
To control which version of IGMP is running on an interface, enter the following command:
hostname(config-if)# igmp version {1 | 2}
Configuring Stub Multicast Routing
A security appliance acting as the gateway to the stub area does not need to participate in PIM. Instead,
you can configure it to act as an IGMP proxy agent and forward IGMP messages from hosts connected
on one interface to an upstream multicast router on another. To configure the security appliance as an
IGMP proxy agent, forward the host join and leave messages from the stub area interface to an upstream
interface.
To forward the host join and leave messages, enter the following command from the interface attached
to the stub area:
hostname(config-if)# igmp forward interface if_name
Note
Stub Multicast Routing and PIM are not supported concurrently.
Configuring a Static Multicast Route
When using PIM, the security appliance 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.