Configuring Igmp Snooping; Default Igmp Snooping Configuration; Enabling Or Disabling Igmp Snooping - Cisco Catalyst 2928 Software Configuration Manual

Configuring IGMP Snooping

Configuring IGMP Snooping
IGMP snooping allows switches to examine IGMP packets and make forwarding decisions based on their
content. These sections contain this configuration information:
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Default IGMP Snooping Configuration

Table 21-3
Table 21-3
Feature
IGMP snooping
Multicast routers
Multicast router learning (snooping) method
IGMP snooping Immediate Leave
Static groups
TCN
TCN query solicitation
IGMP snooping querier
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.
Catalyst 2928 Switch Software Configuration Guide
21-6
Default IGMP Snooping Configuration, page 21-6
Enabling or Disabling IGMP Snooping, page 21-6
Setting the Snooping Method, page 21-7
Configuring a Multicast Router Port, page 21-8
Configuring a Host Statically to Join a Group, page 21-9
Enabling IGMP Immediate Leave, page 21-9
Configuring the IGMP Leave Timer, page 21-10
Configuring TCN-Related Commands, page 21-11
Configuring the IGMP Snooping Querier, page 21-13
Disabling IGMP Report Suppression, page 21-14
shows the default IGMP snooping configuration.
Default IGMP Snooping Configuration
1
flood query count
Chapter 21 Configuring IGMP Snooping
Default Setting
Enabled globally and per VLAN
None configured
PIM-DVMRP
Disabled
None configured
2
Disabled
Disabled
Enabled
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