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Catalyst 2975 Switch Software Configuration Guide
OL-19720-02
Chapter 22 Configuring IGMP Snooping and MVR
Configuring IGMP Snooping
Beginning in privileged EXEC mode, follow these steps to enable IGMP snooping on a VLAN interface:
To disable IGMP snooping on a VLAN interface, use the
no ip igmp snooping vlan
vlan-id
global
configuration command for the specified VLAN number
.
Setting the Snooping Method
Multicast-capable router ports are added to the forwarding table for every Layer 2 multicast entry. The
switch learns of such ports through one of these methods:
•
Snooping on IGMP queries, Protocol Independent Multicast (PIM) packets, and Distance Vector
Multicast Routing Protocol (DVMRP) packets
•
Listening to Cisco Group Management Protocol (CGMP) packets from other routers
•
Statically connecting to a multicast router port with the
ip igmp snooping mrouter
global
configuration command
You can configure the switch either to snoop on IGMP queries and PIM/DVMRP packets or to listen to
CGMP self-join or proxy-join packets. By default, the switch snoops on PIM/DVMRP packets on all
VLANs. To learn of multicast router ports through only CGMP packets, use the
ip igmp snooping vlan
vlan-id
mrouter learn cgmp
global configuration command. When this command is entered, the router
listens to only CGMP self-join and CGMP proxy-join packets and to no other CGMP packets. To learn
of multicast router ports through only PIM-DVMRP packets, use the
ip igmp snooping vlan
vlan-id
mrouter learn pim-dvmrp
global configuration command.
Note
If you want to use CGMP as the learning method and no multicast routers in the VLAN are CGMP
proxy-enabled, you must enter the
ip cgmp router-only
command to dynamically access the router.
Command
Purpose
Step 1
configure terminal
Enter global configuration mode.
Step 2
ip igmp snooping vlan
vlan-id
Enable IGMP snooping on the VLAN interface.The VLAN ID range
is 1 to 1001 and 1006 to 4094.
Note
IGMP snooping must be globally enabled before you can
enable VLAN snooping.
Step 3
end
Return to privileged EXEC mode.
Step 4
copy running-config startup-config
(Optional) Save your entries in the configuration file.
Содержание 2975 - Catalyst LAN Base Switch
Страница 36: ...Contents xxxvi Catalyst 2975 Switch Software Configuration Guide OL 19720 02 ...
Страница 40: ...xxxviii Catalyst 2975 Switch Software Configuration Guide OL 19720 02 Preface ...
Страница 62: ...1 22 Catalyst 2975 Switch Software Configuration Guide OL 19720 02 Chapter 1 Overview Where to Go Next ...
Страница 398: ...13 30 Catalyst 2975 Switch Software Configuration Guide OL 19720 02 Chapter 13 Configuring VLANs Configuring VMPS ...
Страница 424: ...15 18 Catalyst 2975 Switch Software Configuration Guide OL 19720 02 Chapter 15 Configuring VTP Monitoring VTP ...
Страница 628: ...26 8 Catalyst 2975 Switch Software Configuration Guide OL 19720 02 Chapter 26 Configuring UDLD Displaying UDLD Status ...
Страница 660: ...28 8 Catalyst 2975 Switch Software Configuration Guide OL 19720 02 Chapter 28 Configuring RMON Displaying RMON Status ...
Страница 888: ...38 32 Catalyst 2975 Switch Software Configuration Guide OL 19720 02 Chapter 38 Troubleshooting Troubleshooting Tables ...