Igmp Configuration; Cli Example; Igmp Proxy - Dell PowerConnect M6348 Configuration Manual

IGMP Configuration

The Internet Group Management Protocol (IGMP) is used by IPv4 hosts to send requests to join (or
leave) multicast groups so that they receive (or discontinue receiving) packets sent to those groups.
In IPv4 multicast networks, multicast routers are configured with IGMP so that they can receive join and
leave request from directly-connected hosts. They use this information to build a multicast forwarding
table.
IPv6 multicast routers use the MLD protocol to perform the functions that IGMP performs in IPv4
networks.

CLI Example

The following example configures IGMP on a PowerConnect M6220/M6348/M8024 switch. IP routing, IP
multicasting, and IGMP are globally enabled on the router. Then, IGMP is configured on the selected
interface(s).
console#configure
ip routing
ip multicast
ip igmp
interface vlan 2
routing
ip address 3.3.3.1 255.255.255.0
ip igmp
exit
exit
A multicast router must also have a way to determine how to efficiently forward multicast packets. The
information gathered by IGMP is provided to a multicast routing protocol (i.e., DVMRP , PIM-DM, and
PIM-SM) configured on the router to ensure that multicast packets are delivered to all networks where
there are interested receivers. Refer to those sections for configuration instructions.

IGMP Proxy

IGMP proxy enables a multicast router to learn multicast group membership information and forward
multicast packets based upon the group membership information. The IGMP Proxy is capable of
functioning only in certain topologies that do not require Multicast Routing Protocols (i.e., DVMRP,
PIM-DM, and PIM-SM) and have a tree-like topology, as there is no support for features like reverse path
forwarding (RPF) to correct packet route loops.
The proxy contains many downstream interfaces and a unique upstream interface explicitly configured.
It performs the host side of the IGMP protocol on its upstream interface and the router side of the IGMP
protocol on its downstream interfaces.
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Multicast