Configuring Igmp Snooping; Default Igmp Snooping Configuration; Enabling Or Disabling Igmp Snooping - Cisco 3845 - Security Bundle Router Software Manual

Configuring IGMP Snooping

Configuring IGMP Snooping
IGMP snooping allows switches to examine IGMP packets and make forwarding decisions based on their
content.
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Default IGMP Snooping Configuration

Table 18-3
Feature
IGMP snooping
Multicast routers
Multicast router learning (snooping) method
IGMP snooping Immediate Leave
Static groups
TCN
TCN query solicitation
IGMP report suppression
1. TCN = Topology Change Notification

Enabling or Disabling IGMP Snooping

By default, IGMP snooping is globally enabled on the switch. When globally enabled or disabled, it is
also enabled or disabled in all existing VLAN interfaces. IGMP snooping is by default enabled on all
VLANs, but can be enabled and disabled on a per-VLAN basis.
Global IGMP snooping overrides the VLAN IGMP snooping. If global snooping is disabled, you cannot
enable VLAN snooping. If global snooping is enabled, you can enable or disable VLAN snooping.
Beginning in privileged EXEC mode, follow these steps to globally enable IGMP snooping on the
switch:
Command
Step 1 configure terminal
Step 2 ip igmp snooping
Cisco ME 3800X and 3600X Switch Software Configuration Guide
18-6
Default IGMP Snooping Configuration, page 18-6
Enabling or Disabling IGMP Snooping, page 18-6
Configuring a Multicast Router Port, page 18-7
Configuring a Host Statically to Join a Group, page 18-8
Enabling IGMP Immediate Leave, page 18-8
Configuring the IGMP Leave Timer, page 18-9
Configuring TCN-Related Commands, page 18-10
Disabling IGMP Report Suppression, page 18-12
Default IGMP Snooping Configuration
1
flood query count
Purpose
Enter global configuration mode.
Globally enable IGMP snooping in all existing VLAN interfaces.
Chapter 18
Default Setting
Enabled globally and per VLAN
None configured
PIM
Disabled
None configured
2
Disabled
Enabled
Configuring IGMP Snooping
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