Configuring igmp snooping querier, Enabling igmp snooping querier – H3C Technologies H3C S12500 Series Switches User Manual
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Step Command
Remarks
2.
Enter Layer 2 Ethernet
interface view or Layer 2
aggregate interface view, or
enter port group view.
•
Enter Layer 2 Ethernet interface
view or Layer 2 aggregate
interface view:
interface interface-type
interface-number
•
Enter port group view:
port-group manual
port-group-name
Use either method.
3.
Disable the port from
becoming a dynamic router
port.
igmp-snooping router-port-deny
[ vlan vlan-list ]
By default, a port can become a
dynamic router port.
NOTE:
This configuration does not affect the static router port configuration.
Configuring IGMP snooping querier
Before you configure IGMP snooping querier, complete the following tasks:
•
Enable IGMP snooping in the VLAN.
•
Determine the IGMP general query interval.
•
Determine the IGMP last-member query interval.
•
Determine the maximum response delay for IGMP general queries.
•
Determine the source address of IGMP general queries.
•
Determine the source address of IGMP group-specific queries.
Enabling IGMP snooping querier
In an IP multicast network that runs IGMP, a multicast router or Layer 3 multicast switch sends IGMP
queries, so that all Layer 3 multicast devices can establish and maintain multicast forwarding entries, in
order to forward multicast traffic correctly at the network layer. This router or Layer 3 switch is called the
"IGMP querier." For more information about IGMP querier, see "Configuring IGMP."
However, a Layer 2 multicast switch does not support IGMP, and therefore cannot send general queries
by default. When you enable IGMP snooping querier on a Layer 2 switch in a VLAN where multicast
traffic is switched only at Layer 2 and no multicast routers are present, the Layer 2 switch sends IGMP
queries, so that multicast forwarding entries can be established and maintained at the data link layer.
IMPORTANT:
Do not configure an IGMP snooping querier in a multicast network running IGMP. Although an IGMP
snooping querier does not take part in IGMP querier elections, it might affect IGMP querier elections
because it sends IGMP general queries with a low source IP address.
To enable IGMP snooping querier: