Default Configuration In Ip Multicast Routing; Enabling Ip Multicast Routing; Enabling Pim On An Interface - Cisco 4500M Software Manual

Chapter 25 Understanding and Configuring IP Multicast

Default Configuration in IP MUlticast Routing

Table 25-1
Table 25-1 Default IP Multicast Configuration
Feature
Rate limiting of RPF
IP multicast routing
PIM
IGMP snooping
Source-specific multicast and IGMP v3 are supported.
Note
For more information about source-specific multicast with IGMPv3 and IGMP, see the following URL:
http://www.cisco.com/univercd/cc/td/doc/product/software/ios122/122cgcr/fipr_c/ipcpt3/1cfssm.htm

Enabling IP Multicast Routing

Enabling IP multicast routing allows the Catalyst 4500 series switch to forward multicast packets. To
enable IP multicast routing on the router, perform this task in global configuration mode:
Command
Switch(config)# ip multicast-routing

Enabling PIM on an Interface

Enabling PIM on an interface also enables IGMP operation on that interface. An interface can be
configured to be in dense mode, sparse mode, or sparse-dense mode. The mode determines how the
Layer 3 switch or router populates its multicast routing table and how the Layer 3 switch or router
forwards multicast packets it receives from its directly connected LANs. You must enable PIM in one of
these modes for an interface to perform IP multicast routing.
OL-6696-01
shows the IP multicast default configuration.
Default Value
Enabled globally
Disabled globally
Note When IP multicast routing is disabled, IP multicast traffic data
packets are not forwarded by the Catalyst 4500 series switch.
However, IP multicast control traffic will continue to be processed
and forwarded. Therefore, IP multicast routes can remain in the
routing table even if IP multicast routing is disabled.
Disabled on all interfaces
Enabled on all VLAN interfaces
If you disable IGMP snooping on an interface, all output ports are
Note
forwarded by the Integrated Switching Engine. When IGMP
snooping is disabled on an input VLAN interface, multicast packets
related to that interface are sent to all forwarding switchports in the
VLAN.
Configuring IP Multicast Routing
Purpose
Enables IP multicast routing.
Software Configuration Guide—Release 12.2(25)EW
25-13