Igmpv1 And Igmpv2 - Cisco AJ732A - MDS 9134 Fabric Switch Configuration Manual

Information About IGMP Snooping
S e n d f e e d b a c k t o n x 5 0 0 0 - d o c f e e d b a c k @ c i s c o . c o m
Figure 14-1
Note The switch supports IGMPv3 snooping based only on the destination multicast MAC address. It does not
support snooping based on the source MAC address or on proxy reports.
The Cisco NX-OS IGMP snooping software supports optimized multicast flooding (OMF) that forwards
unknown traffic to routers only and performs no data driven state creation. For more information about
IGMP snooping, see
This section includes the following topics:
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IGMPv1 and IGMPv2

Both IGMPv1 and IGMPv2 support membership report suppression, which means that if two hosts on
the same subnet want to receive multicast data for the same group, then the host that receives a member
report from the other host suppresses sending its report. Membership report suppression occurs for hosts
that share a port.
If no more than one host is attached to each VLAN switch port, then you can configure the fast leave
feature in IGMPv2. The fast leave feature does not send last member query messages to hosts. As soon
as the software receives an IGMP leave message, the software stops forwarding multicast data to that
port.
IGMPv1 does not provide an explicit IGMP leave message, so the software must rely on the membership
message timeout to indicate that no hosts remain that want to receive multicast data for a particular
group.
Note Cisco NX-OS ignores the configuration of last member query interval when you enable the fast leave
feature because it does not check for remaining hosts.
Cisco Nexus 5000 Series Switch CLI Software Configuration Guide
14-2
IGMP Snooping Switch
IGMP Router
IGMP Query Messages
IGMP Snooping Switch
IGMP Report and Leave Messages
Host
RFC 4541.
IGMPv1 and IGMPv2, page 14-2
IGMPv3, page 14-3
IGMP Snooping Querier, page 14-3
IGMP Forwarding, page 14-3
Chapter 14 Configuring IGMP Snooping
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