BFD in a VMware NSX for vSphere environment with OVSDB and VXLAN

Within a Virtual Extensible LAN (VXLAN) managed by the Open vSwitch Database (OVSDB) protocol, by default, Layer 2 broadcast, unknown unicast, and multicast (BUM) traffic is replicated and forwarded by one or more software virtual tunnel endpoints (VTEPs) or service nodes in the same VXLAN. (The software VTEPs and service nodes are collectively referred to as replicators.) A Juniper Networks switch that functions as a hardware VTEP in a VMware NSX for vSphere (NSX-v) environment uses the Bidirectional Forwarding Detection (BFD) protocol to prevent the forwarding of BUM packets to a nonfunctional replicator. By exchanging BFD control messages with replicators at regular intervals, the hardware VTEP can monitor the replicators to ensure that they are functioning and are, therefore, reachable. Upon receipt of a BUM packet on an OVSDB-managed interface, the hardware VTEP can choose one of the functioning replicators to handle the packet.