Enabling Local Egress Replication - Cisco 7604 Configuration Manual

Configuring IPv4 Multicast Layer 3 Switching

Enabling Local Egress Replication

Supervisor Engine 32 and Supervisor Engine 2 support only ingress replication mode.
Note
With a Supervisor Engine 720, Release 12.2(18)SXF and later releases allow you to unconditionally
enable local egress replication. This feature is called "Multicast enhancement - egress replication
performance improvement" in the release notes and Feature Navigator.
DFC-equipped modules with dual switch-fabric connections host two packet replication engines, one per
fabric connection. Each replication engine is responsible for forwarding packets to and from the
interfaces associated with the switch-fabric connections. The interfaces that are associated with a
switch-fabric connection are considered to be "local" from the perspective of the packet replication
engine.
With Release 12.2(18)SXF and later releases, you can prevent redundant replication of multicast packets
across the switch-fabric connection by entering a command that instructs the two replication engines on
these modules to forward packets only to local interfaces which are associated with the switch-fabric
connection that the replication engine supports.
When you enable this feature, the multicast expansion table (MET) for each replication engine is
populated with the local Layer 3 interfaces only. This action prevents replication for interfaces that are
not supported by the replication engine (nonlocal interfaces) and increases replication performance.
Local egress replication is supported with the following software configuration and hardware:
•
•
•
The local egress replication feature is not supported for the following internal VLANs:
•
•
•
•
•
The local egress replication feature is not supported with IPv6 multicast or in a system that has a mix of
Note
IPv4 and IPv6 multicast enabled.
To enable local egress replication, perform this task:
Command
Step 1
Router(config)# mls ip multicast egress local
Step 2
Router # reload
Step 3
Router# show mls ip multicast capability
Router# show mls cef ip multicast detail
Cisco 7600 Series Router Cisco IOS Software Configuration Guide, Release 12.2SX
28-14
IPv4 egress replication mode
Dual fabric-connection DFC-equipped modules
Layer 3-routed interfaces and subinterfaces that are not part of a port channel
Egress internal VLAN
Partial-shortcut internal VLAN
Internal VLAN for Multicast VPN Multicast Distribution Tree (MDT) tunnel
Point-to-point tunnel internal VLAN
QoS internal VLAN
Chapter 28 Configuring IPv4 Multicast Layer 3 Switching
Purpose
Enables local egress replication.
This command requires a system reset for the
Note
configuration to take effect.
Reloads the system.
Displays the configured replication mode.
OL-4266-08