Configuring MLD snooping
Overview
MLD snooping runs on a Layer 2 switch as an IPv6 multicast constraining mechanism to improve multicast forwarding efficiency. It creates Layer 2 multicast forwarding entries from MLD messages that are exchanged between the hosts and the router.
As shown in Figure 241, when MLD snooping is not enabled, the Layer 2 switch floods IPv6 multicast packets to all hosts. When MLD snooping is enabled, the Layer 2 switch forwards multicast packets of known IPv6 multicast groups to only the receivers of the multicast groups.
Figure 241 IPv6 multicast forwarding before and after MLD snooping is enabled
Basic MLD snooping concepts
This section lists the basic MLD snooping concepts.
MLD snooping related ports
As shown in Figure 242, MLD snooping runs on Switch A and Switch B. Host A and Host C are receivers in an IPv6 multicast group.
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