Cisco 3845 - Security Bundle Router Software Guide

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Cisco ME 3800X and 3600X Switch Software Configuration Guide
OL-23400-01
Chapter 18 Configuring IGMP Snooping
Displaying IGMP Snooping Information
Disabling IGMP Report Suppression
Note IGMP report suppression is supported only when the multicast query has IGMPv1 and IGMPv2 reports.
This feature is not supported when the query includes IGMPv3 reports.
IGMP report suppression is enabled by default. When it is enabled, the switch forwards only one IGMP
report per multicast router query. When report suppression is disabled, all IGMP reports are forwarded
to the multicast routers.
Beginning in privileged EXEC mode, follow these steps to disable IGMP report suppression:
To re-enable IGMP report suppression, use the ip igmp snooping report-suppression global
configuration command.
Displaying IGMP Snooping Information
You can display IGMP snooping information for dynamically learned and statically configured router
ports and VLAN interfaces. You can also display MAC address multicast entries for a VLAN configured
for IGMP snooping.
To display IGMP snooping information, use one or more of the privileged EXEC commands in
Table 18-4.
Command Purpose
Step 1
configure terminal Enter global configuration mode.
Step 2
no ip igmp snooping report-suppression Disable IGMP report suppression.
Step 3
end Return to privileged EXEC mode.
Step 4
show ip igmp snooping Verify that IGMP report suppression is disabled.
Step 5
copy running-config startup-config (Optional) Save your entries in the configuration file.
Table 18-4 Commands for Displaying IGMP Snooping Information
Command Purpose
show ip igmp snooping [vlan vlan-id] Display the snooping configuration information for all VLANs on the
switch or for a specified VLAN.
(Optional) Enter vlan vlan-id to display information for a single VLAN.
The VLAN ID range is 1 to 1001 and 1006 to 4094.
show ip igmp snooping groups [count |dynamic
[count] | user [count]]
Display multicast table information for the switch or about a specific
parameter:
• count—Display the total number of entries for the specified
command options instead of the actual entries.
• dynamic—Display entries learned through IGMP snooping.
• user—Display only the user-configured multicast entries.

Cisco 3845 - Security Bundle Router Specifications

General

Brand	Cisco
Model	3845 - Security Bundle Router
Category	Switch
Language	English