Your multicast receivers are indirectly connected to an MX Series router. The receivers need to join multicast group 224.2.2.2. What must be configured in IGMP to receive report messages from receivers that are multiple hops away?
A.
By default, IGMP accepts report messages from indirectly connected receivers.
B.
Promiscuous mode must be enabled in IGMP.
C.
Promiscuous mode must be disabled in IGMP.
D.
DVMRP protocol must be configured.
Answer is B
Promiscuous mode must be enabled in IGMP.
http://www.juniper.net/techpubs/en_US/junos13.2/topics/topic-map/mcast-igmp.html
Accepting IGMP Messages from Remote Subnetworks
By default, IGMP interfaces accept IGMP messages only from the same subnet. Including the promiscuous-mode statement enables the routing device to accept IGMP messages from indirectly connected subnets.
Note: When you enable IGMP on an unnumbered Ethernet interface that uses a /32 loopback address as a donor address, you must configure IGMP promiscuous mode to accept the IGMP packets received on this interface.
Note: When enabling promiscuous-mode, all routers on the ethernet segment must be configured with the promiscuous mode statement. Otherwise, only the interface configured with lowest IPv4 address acts as the querier for IGMP for this Ethernet segment.
To enable IGMP promiscuous mode on an interface:
Configure the IGMP interface.
[edit protocols igmp]
user@host# set interface ge-0/1/1.0 promiscuous-mode
Verify the configuration by checking the Promiscuous Mode field in the output of the show igmp interface command.
Verify the operation of the filter by checking the Rx non-local field in the output of the show igmp statistics command.