The igmp-snooping proxy router-protocol-pass command configures an IGMP Snooping Proxy-enabled device to transparently transmit IGMP Report messages.
The undo igmp-snooping proxy router-protocol-pass command cancels the configuration.
By default, an IGMP Snooping Proxy-enabled device does not transparently transmit received IGMP Report messages.
Usage Scenario
If IGMP Snooping Proxy is enabled on a Layer 2 device and its upstream device, these devices will learn same multicast forwarding entries. As a result, the upstream device constantly sends Query messages, and the downstream device constantly responds to the Query messages, causing multicast entries not to age. Consequently, multicast protocol and data packets are forwarded meaninglessly. After the igmp-snooping proxy router-protocol-pass command is run on a device, the device does not terminate received IGMP Report messages, but transparently transmits IGMP Report messages received from one of its router ports to the other router ports.
The igmp-snooping proxy router-protocol-pass command is recommended on a network where an IGMP Snooping Proxy-enabled device is dual-homed to upstream devices.Prerequisites
The igmp-snooping proxy command has been run to enable IGMP Snooping Proxy in a BD.
Configuration Impact
Running the igmp-snooping proxy router-protocol-pass command changes the action taken by an IGMP Snooping Proxy-enabled device on IGMP Report messages received from a router port. The device does not terminate IGMP Report messages received from this router port but forwards these messages upstream.