Exam JN0-649 topic 1 question 15 discussion

It is about how EVPN handle BUM traffic. The source leaf will send the unknown unicast traffic to all leaf that with same VLAN/VTEP.

10.0.0.127 is the broadcast address for 10.0.0.0/25. Ingress replication leads to answer B and C.

correct answer: B. Router C will send a VXLAN packet destined only to router D and router E. C. Router D will not replicate and send a copy of the received VXLAN packet to router E.

The source leaf (C) will send the broadcast traffic to all VTEPs of leafs that with same VLAN (D and E). those routers will not forward it again...

bc is correct

BC is correct, ingress BUM traffic would be sent by local PE, other PEs will not replicate BUM traffic to remote PEs

Router E will replicate and send a copy of the received VXLAN packet to router D Ingress Replication Ingress replication involves an ingress device replicating every incoming BUM packet and sending them as a separate unicast to the remote egress devices. Ingress replication happens through EVPN route type 3, also called as inclusive multicast ethernet tag (IMET) route

Router C will send a VXLAN packet destined only to router D and router E Underlay Multicast: In underlay multicast, the underlay network replicates the traffic through a multicast group. Forwarding BUM traffic using underlay multicast requires the configuration of IP multicast in the underlay network. A single copy of the BUM traffic moves from the ingress or source VTEP towards the underlay transport network. The network forwards this copy along the multicast tree so that it reaches all egress or destination VTEPs participating in the given multicast group.