Overview of IGMP
This chapter describes multimedia traffic control with IP multicast—Internet Group Management Protocol (IGMP).
IGMP reduces unnecessary bandwidth usage on a per-port basis.
More information
IGMP general operation and features on page 29
Enabling IGMP
IGMP is disabled in the default factory configuration. To enable:
Procedure
1.
If multiple VLANs are not configured:
Configure IGMP on the default VLAN (DEFAULT_VLAN; VID=1.)
2.
If multiple VLANs are configured:
Configure IGMP on a per-VLAN basis for every VLAN where the feature is of use.
Configuring and displaying IGMP (CLI)
show ip igmp vlan
Syntax
show ip igmp vlan
vid
Description
Displays IGMP configuration for a specified VLAN or for all VLANs on the switch.
Example output
switch(config)# show ip igmp vlan 1
IGMP Service Protocol Info
Total VLANs with IGMP enabled : 30
Current count of multicast groups joined : 20
VLAN ID : 2
VLAN Name : VLAN2
IGMP version : 2
Querier Address : 10.255.128.2
Querier Port : A1
Querier UpTime : 1h 51m 59s
Querier Expiration Time : 2min 5sec
Ports with multicast routers: A1, A5-A6
Active Group Addresses Type Expires Ports Reports Queries
---------------------- ---------- --------------- ---------- ------- -------
Chapter 2
Multimedia traffic control with IP multicast (IGMP)
Chapter 2 Multimedia traffic control with IP multicast (IGMP)
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