Leaving A Multicast Group - Cisco 7604 Configuration Manual

Understanding How MLDv2 Snooping Works
Figure 29-2 Second Host Joining a Multicast Group
Table 29-2 Updated MLDv2 Snooping Forwarding Table
Destination MAC Address
0100.5exx.xxxx
0100.5e01.0203

Leaving a Multicast Group

These sections describe leaving a multicast group:
•
•
Normal Leave Processing
Interested hosts must continue to respond to the periodic MLDv2 general queries. As long as at least one
host in the VLAN responds to the periodic MLDv2 general queries, the multicast router continues
forwarding the multicast traffic to the VLAN. When hosts want to leave a multicast group, they can
either ignore the periodic MLDv2 general queries (called a "silent leave"), or they can send an MLDv2
filter mode change record.
When MLDv2 snooping receives a filter mode change record from a host that configures the EXCLUDE
mode for a group, MLDv2 snooping sends out a MAC-addressed general query to determine if any other
hosts connected to that interface are interested in traffic for the specified multicast group.
If MLDv2 snooping does not receive an MLDv2 report in response to the general query, MLDv2
snooping assumes that no other hosts connected to the interface are interested in receiving traffic for the
specified multicast group, and MLDv2 snooping removes the interface from its Layer 2 forwarding table
entry for the specified multicast group.
Cisco 7600 Series Router Cisco IOS Software Configuration Guide, Release 12.2SX
29-6
PFC
CPU
0
Forwarding
table
2 3
Host 1 Host 2
Normal Leave Processing, page 29-6
Fast-Leave Processing, page 29-7
Chapter 29
Router A
1
VLAN
4 5
Host 3 Host 4
Type of Packet Ports
MLDv2 0
!MLDv2 1, 2, 5
Configuring MLDv2 Snooping for IPv6 Multicast Traffic
OL-4266-08