A company wants to deploy VMware NSX for vSphere with no PIM and no IGMP configured in the
underlying physical network. This company also must ensure that non-ESXi hosts do not receive
broadcast, unknown unicast or multicast (BUM) traffic.
Which replication mode should the logical switches be deployed with?
A.
Unicast Replication Mode
B.
Multicast Replication Mode
C.
Hybrid Replication Mode
D.
Transport Zone Mode
Unicast Mode represents a completely opposite approach than multicast mode, where the decoupling between logical and physical networks is fully achieved. In Unicast Mode, the ESXi hosts in the NSX domain are divided in separate groups (VTEP segments) based on the IP subnet their VTEP interfaces belong to. An ESXi host in each VTEP segment is selected to play the role of Unicast Tunnel End Point (UTEP).
The UTEP is responsible for replicating multidestination traffic received from the ESXi hypervisor hosting the VM sourcing the traffic and belonging to a different
VTEP segment to all the ESXi hosts part of its segment (i.e. whose VTEPs belong to the same subnet of the UTEP’s VTEP interface).
In order to optimize the replication behavior, every UTEP will only replicate traffic to ESXi hosts on the local segment that have at least one VM actively connected to the logical network where multi-destination traffic is sent to. In the same way, traffic will only be sent by the source ESXi to the remote UTEPs if there is at least one active VM connected to an ESXi host in that remote segment.