Igmp Snooping Querier Configuration Guidelines And Restrictions; Enabling The Igmp Snooping Querier - Cisco WS-SUP32-GE-3B - Supervisor Engine 32 Software Configuration Manual

IGMP Snooping Querier Configuration Guidelines and Restrictions

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IGMP Snooping Querier Configuration Guidelines and
Restrictions
When configuring the IGMP snooping querier, follow these guidelines and restrictions:
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Note When you are in configuration mode you can enter EXEC mode commands by entering the do keyword
before the EXEC mode command.

Enabling the IGMP Snooping Querier

Use the IGMP snooping querier to support IGMP snooping in a VLAN where PIM and IGMP are not
configured because the multicast traffic does not need to be routed.
To enable the IGMP snooping querier in a VLAN, perform this task:
Command
Step 1
Router(config)# interface vlan vlan_ID
Step 2
Router(config-if)# ip address ip_address
subnet_mask
Catalyst Supervisor Engine 32 PISA Cisco IOS Software Configuration Guide, Release 12.2ZY
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For more information on IP multicast and IGMP, refer to RFC 1112 and RFC 2236.
IGMP snooping supports private VLANs. Private VLANs do not impose any restrictions on IGMP
snooping.
IGMP snooping constrains traffic in MAC multicast groups 0100.5e00.0001 to 0100.5eff.ffff.
IGMP snooping does not constrain Layer 2 multicasts generated by routing protocols.
Configure the VLAN in global configuration mode (see
Configure an IP address on the VLAN interface (see
When enabled, the IGMP snooping querier uses the IP address as the query source address.
If there is no IP address configured on the VLAN interface, the IGMP snooping querier does not
start. The IGMP snooping querier disables itself if the IP address is cleared. When enabled, the
IGMP snooping querier restarts if you configure an IP address.
The IGMP snooping querier supports IGMP version 2.
When enabled, the IGMP snooping querier does not start if it detects IGMP traffic from a multicast
router.
When enabled, the IGMP snooping querier starts after 60 seconds with no IGMP traffic detected
from a multicast router.
When enabled, the IGMP snooping querier disables itself if it detects IGMP traffic from a multicast
router.
QoS does not support IGMP packets when IGMP snooping is enabled.
You can enable the IGMP snooping querier on all the Catalyst 6500 series switches in the VLAN.
One switch is elected as the querier.
Chapter 27 Configuring IGMP Snooping for IPv4 Multicast Traffic
Chapter 12, "Configuring
Chapter 19, "Configuring Layer 3
Purpose
Selects the VLAN interface.
Configures the IP address and IP subnet.
VLANs").
Interfaces").
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