Igmp Snooping Querier; Cli Examples - Dell PowerConnect M6348 Configuration Manual

Example #3: Show IGMP Snooping Information for an Interface
console#show ip igmp snooping interface ethernet 1/g17
Slot/Port...................................... 1/g17
Global IGMP Snooping Admin Mode................ Enabled
IGMP Snooping Admin Mode....................... Enabled
Fast Leave Mode................................ Disabled
Group Membership Interval...................... 260
Max Response Time.............................. 10
Multicast Router Present Expiration Time....... 300

IGMP Snooping Querier

When PIM and IGMP are enabled in a network with IP multicast routing, the IP multicast router acts as
the IGMP querier. However, if the IP-multicast traffic in a VLAN needs to be Layer 2 switched only, an
IP-multicast router is not required. The IGMP Snooping Querier can perform the IGMP snooping
functions on the VLAN.
NOTE:
Without an IP-multicast router on a VLAN, you must configure another switch as the IGMP querier so that it
can send queries.
When the IGMP snooping querier is enabled, the IGMP snooping querier sends out periodic IGMP
queries that trigger IGMP report messages from the switch that wants to receive IP multicast traffic. The
IGMP snooping feature listens to these IGMP reports to establish appropriate forwarding.

CLI Examples

The following examples show commands to use with the IGMP Snooping Querier feature.
Example #1: Enable IGMP Snooping Querier on the Switch
The first command in this example enables the IGMP snooping querier on the switch. The second
command specifies the IP address that the snooping querier switch should use as the source address
when generating periodic queries.
console(config)#ip igmp snooping
console(config)#ip igmp snooping querier
console(config)#ip igmp snooping querier address 10.10.20.12
NOTE:
The IGMP snooping must be enabled for the IGMP snooping querier function to operate.
Example #2: Configure IGMP Snooping Querier Properties
The first command in this example sets the IGMP Querier Query Interval time to 100. This means that
the switch waits 100 seconds before sending another general query. The second command sets the IGMP
Querier timer expiration period to 100. This means that the switch remains in Non-Querier mode for
100 seconds after it has discovered that there is a Multicast Querier in the network.
Switching Configuration
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