15-17
Catalyst 2360 Switch Software Configuration Guide
OL-19808-01
Chapter 15 Configuring IGMP Snooping
Configuring IGMP Filtering and Throttling
IGMP filtering controls only group-specific query and membership reports, including join and leave
reports. It does not control general IGMP queries. IGMP filtering has no relationship with the function
that directs the forwarding of IP multicast traffic. The filtering feature uses CGMP to forward the
multicast traffic.
IGMP filtering is applicable only to the dynamic learning of IP multicast group addresses, not static
configuration.
With the IGMP throttling feature, you can set the maximum number of IGMP groups that a Layer 2
interface can join. If the maximum number of IGMP groups is set, the IGMP snooping forwarding table
contains the maximum number of entries, and the interface receives an IGMP join report, you can
configure an interface to drop the IGMP report or to replace the randomly selected multicast entry with
the received IGMP report.
Note
IGMPv3 join and leave messages are not supported on switches running IGMP filtering.
These sections contain this configuration information:
•
Default IGMP Filtering and Throttling Configuration, page 15-17
•
Configuring IGMP Profiles, page 15-18
(optional)
•
Applying IGMP Profiles, page 15-19
(optional)
•
Setting the Maximum Number of IGMP Groups, page 15-19
(optional)
•
Configuring the IGMP Throttling Action, page 15-20
(optional)
Default IGMP Filtering and Throttling Configuration
shows the default IGMP filtering configuration.
When the maximum number of groups is in forwarding table, the default IGMP throttling action is to
deny the IGMP report. For configuration guidelines, see the
“Configuring the IGMP Throttling Action”
Table 15-5
Default IGMP Filtering Configuration
Feature
Default Setting
IGMP filters
None applied
IGMP maximum number of IGMP groups
No maximum set
IGMP profiles
None defined
IGMP profile action
Deny the range addresses