Configuring IPv4 Multicast Layer 3 Switching
To enable IP multicast Layer 3 switching on a Layer 3 interface, perform this task:
Command
Step 1
Router(config)# interface {{vlan vlan_ID } |
1
{ type
slot/port }}
Step 2
Router(config-if)# mls ip multicast
Step 3
Router(config-if)# no mls ip multicast
1.
type = ethernet, fastethernet, gigabitethernet, or tengigabitethernet
This example shows how to enable IP multicast Layer 3 switching on a Layer 3 interface:
Router(config-if)# mls ip multicast
Router(config-if)#
Configuring the Replication Mode
Note
Supervisor Engine 32 and Supervisor Engine 2 support only ingress replication mode.
With a Supervisor Engine 720, Release 12.2(18)SXF and later releases support the egress keyword.
Support for the egress keyword is called "Multicast Enhancement - Replication Mode Detection" in the
release notes and Feature Navigator.
By default, a Supervisor Engine 720 automatically detects the replication mode based on the module
types installed in the system. If all modules are capable of egress replication, the system uses
egress-replication mode. If the supervisor engine detects modules that are not capable of egress
replication, the replication mode automatically changes to ingress replication. You can override this
action by entering the mls ip multicast replication-mode egress command so that the system continues
to work in egress-replication mode even if there are fabric-enabled modules installed that do not support
egress replication (for example, OSMs). You can also configure the system to operate only in
ingress-replication mode.
If the system is functioning in automatic detection mode, and you install a module that cannot perform
egress replication, the following occurs:
•
•
•
If the system is functioning in forced egress mode, a system log is created that will display the presence
of modules that are not capable of egress replication mode.
If you configure forced egress mode in a system that has fabric-enabled modules that are not capable of
Note
egress replication, you must make sure that these modules are not sourcing or receiving multicast traffic.
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28-12
The system reverts to ingress mode
A system log is generated
A system reload occurs to revert to the old configuration
Chapter 28
Configuring IPv4 Multicast Layer 3 Switching
Purpose
Selects an interface to configure.
Enables IP multicast Layer 3 switching on a Layer 3
interface.
Disables IP multicast Layer 3 switching on a Layer 3
interface.
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