Configuring Mvr; Default Mvr Configuration - Cisco Catalyst 2975 Software Configuration Manual

Chapter 22 Configuring IGMP Snooping and MVR
IGMP leave was received. As soon as the leave message is received, the receiver port is removed from
multicast group membership, which speeds up leave latency. Enable the Immediate-Leave feature only
on receiver ports to which a single receiver device is connected.
MVR eliminates the need to duplicate television-channel multicast traffic for subscribers in each VLAN.
Multicast traffic for all channels is only sent around the VLAN trunk once—only on the multicast
VLAN. The IGMP leave and join messages are in the VLAN to which the subscriber port is assigned.
These messages dynamically register for streams of multicast traffic in the multicast VLAN on the
Layer 3 device. Switch B. The access layer switch, Switch A, modifies the forwarding behavior to allow
the traffic to be forwarded from the multicast VLAN to the subscriber port in a different VLAN,
selectively allowing traffic to cross between two VLANs.
IGMP reports are sent to the same IP multicast group address as the multicast data. The Switch A CPU
must capture all IGMP join and leave messages from receiver ports and forward them to the multicast
VLAN of the source (uplink) port, based on the MVR mode.

Configuring MVR

These sections contain this configuration information:
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Default MVR Configuration

Table 22-5
Table 22-5
Feature
MVR
Multicast addresses
Query response time
Multicast VLAN
Mode
Interface (per port) default
Immediate Leave
OL-19720-02
Default MVR Configuration, page 22-19
MVR Configuration Guidelines and Limitations, page 22-20
Configuring MVR Global Parameters, page 22-20
Configuring MVR Interfaces, page 22-21
shows the default MVR configuration.
Default MVR Configuration
Default Setting
Disabled globally and per interface
None configured
0.5 second
VLAN 1
Compatible
Neither a receiver nor a source port
Disabled on all ports
Catalyst 2975 Switch Software Configuration Guide
Configuring MVR
22-19