IGMP snooping is supported in EVPN-MPLS VPLS and PBB-EVPN I-VPLS (where BGP EVPN is running in the associated B-VPLS service) services. It is also supported in EVPN-MPLS VPRN and IES R-VPLS services. It is required in scenarios where the operator does not want to flood all of the IP multicast traffic to the access nodes or CEs, and only wants to deliver IP multicast traffic for which IGMP reports have been received.
The following points apply when IGMP snooping is configured in EVPN-MPLS VPLS or PBB-EVPN I-VPLS services:
IGMP snooping is enabled using the configure service vpls igmp-snooping no shutdown command.
Queries and reports received on SAP or SDP bindings are snooped and properly handled; they are sent to SAP or SDP bindings as expected.
Queries and reports on EVPN-MPLS or PBB-EVPN B-VPLS destinations are handled as follows.
If received from SAP or SDP bindings, the queries and reports are sent to all EVPN-MPLS and PBB-EVPN B-VPLS destinations, regardless of whether the service is using an ingress replication or mLDP provider tunnel.
If received on an EVPN-MPLS or PBB-EVPN B-VPLS destination, the queries and reports are processed and propagated to access SAP or SDP bindings, regardless of whether the service is using an ingress replication or mLDP provider tunnel.
EVPN-MPLS and PBB-EVPN B-VPLS destinations are is treated as a single IGMP snooping interface and is always added as an mrouter.
The debug trace output displays one copy of messages being sent to all EVPN-MPLS and PBB-EVPN B-VPLS destinations (the trace does not show a copy for each destination) and displays messages received from all EVPN-MPLS and PBB-EVPN B-VPLS destinations as coming from a single EVPN-MPLS interface.
In the following show command output, the EVPN-MPLS destinations are shown as part of the MFIB (when igmp-snooping is in a no shutdown state), and the EVPN-MPLS logical interface is shown as an mrouter.
*A:PE-2# show service id 2000 mfib 
===============================================================================
Multicast FIB, Service 2000
===============================================================================
Source Address  Group Address         SAP or SDP Id                   Svc Id   Fwd
                                                                            Blk
-------------------------------------------------------------------------------
*               *                     eMpls:192.0.2.3:262132       Local    Fwd
                                      eMpls:192.0.2.4:262136       Local    Fwd
                                      eMpls:192.0.2.5:262131       Local    Fwd
-------------------------------------------------------------------------------
Number of entries: 1
===============================================================================
*A:PE-2# show service id 2000 igmp-snooping base 
===============================================================================
IGMP Snooping Base info for service 2000
===============================================================================
Admin State : Up
Querier     : 10.0.0.3 on evpn-mpls
-------------------------------------------------------------------------------
SAP or SDP                   Oper MRtr Pim  Send Max   Max  Max   MVR       Num
Id                        Stat Port Port Qrys Grps  Srcs Grp   From-VPLS Grps
                                                         Srcs            
-------------------------------------------------------------------------------
sap:1/1/1:2000            Up   No   No   No   None  None None  Local     0
evpn-mpls                 Up   Yes  N/A  N/A  N/A   N/A  N/A   N/A       N/A
===============================================================================
*A:PE-4# show service id 2000 igmp-snooping mrouters 
 
===============================================================================
IGMP Snooping Multicast Routers for service 2000
===============================================================================
MRouter          SAP or SDP Id                 Up Time        Expires   Version
-------------------------------------------------------------------------------
10.0.0.3         evpn-mpls                  0d 00:38:49    175s      3
-------------------------------------------------------------------------------
Number of mrouters: 1
===============================================================================
The equivalent output for PBB-EVPN services is similar to the output above for EVPN-MPLS services, with the exception that the EVPN destinations are named "b-EVPN-MPLS".