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10
C
ONFIGURING
IGMP S
NOOPING
This section contains information for configuring IGMP Snooping and
IGMP Query.
When IGMP Snooping is enabled globally, all IGMP packets are forwarded
to the CPU. The CPU analyzes the incoming packets and determines:
■
Which ports want to join which Multicast groups.
■
Which ports have Multicast routers generating IGMP queries.
Ports requesting to join a specific Multicast group issue an IGMP report,
specifying that Multicast group is accepting members. This results in the
creation of the Multicast filtering database.
If IGMP Query is enabled and this switch is elected as the querier for the
local LAN segment, it will periodically poll each known multicast group
for active members, and dynamically configure the switch ports which
need to forward multicast traffic. It then propagates the service requests
on to any upstream multicast switch/router to ensure that it will continue
to receive the multicast service.
This section contains the following topic:
■
Defining IGMP Snooping and Query