Edge ECMP topology In VMware NSX-T Data Center for VxBlock Systems, ECMP provides load-balancing across multiple paths northbound from the Tier-0s to the ToR switches. VMware NSX-T Data Center supports a maximum of eight paths per edge node cluster. Each Tier-0 gateway peers with each of the two ToR Cisco Nexus 9000 Series Switches. As a result, the maximum number of edge node VMs in the cluster is four. The following figure shows a minimum edge cluster configuration with two edge node VMs peering with the ToR switches, consuming four ECMP paths: The following figure shows a maximum edge node cluster configuration with four edge node VMs peering with the ToR switches, consuming eight ECMP paths: This design peers each edge node with each ToR switch. Child TopicsECMP routing configurationEach Tier-0 gateway peers with each ToR switch using BGP, and traffic is distributed across the available edge node VMs using ECMP. Bi-directional Forwarding DetectionThe Bi-directional Forwarding Detection (BFD) technology detects when a send or receive channel of a network connection is not functioning correctly. Edge node VM resource usage and Data Plane Development KitThe VMware NSX-T Data Center edge node VMs implement the Data Plane Development Kit (DPDK) standard to provide high-performance packet forwarding capabilities. NS-peering edge clusterThe engineered VxBlock System implementation of VMware NSX-T Data Center deploys medium-sized edge VMs for the NS-Peering edge cluster. This cluster carries North-South traffic flows exclusively and must not run any services other than BGP peering and ECMP. The medium appliance meets these requirements. Production01 edge clusterThe production01 edge cluster uses the large-sized edge VM. The production01 cluster hosts various services for the VMware NSX-T Data Center environment, including load balancing, VPN services, NAT, DHCP, and Edge Firewall. These services consume additional resources so use a large-sized edge VM. This cluster should be used only in cases where VMware NSX-T Data Center Tier 1 centralized services are instantiated. Custom edge clustersThe VMware NSX-T Data Center solution for VxBlock Systems includes two edge clusters. Optionally, deploy additional edge VM clusters after initial system deployment. All VMware supported configurations are allowed provided they do not interfere with operation of the original design. The physical edge nodes have sufficient resources to allow an additional large edge node or several small or medium edge nodes per host. Ensure that each of the hosts in the cluster has some reserve capacity. Maintenance and recovery operations can be completed as needed with no warnings or errors appearing in the VMware vCenter Server UI. VRF LiteVMware NSX-T Data Center 3.0 contains a new feature into the VMware NSX-T Data Center UI to configure multiple Virtual Routing and Forwarding (VRF) instances. This feature adds the ability to create separate routing tables for various environments.Using VRF makes it possible to completely separate the routing tables for production, development, and test environments. You can also separate traffic by tenant in a multitenant environment. SegmentsVMware NSX-T Data Center uses GENEVE encapsulation to encapsulate data plane traffic. An Overlay Backed Segment is the VMware NSX-T Data Center equivalent of a port group on a VMware VDS. Transport zonesSegments are created as part of a VMware NSX-T Data Center object called a transport zone. There are VLAN-backed transport zones and overlay-backed transport zones. ProfilesAn uplink profile template defines how an NSX-managed Virtual Distributed Switch (N-VDS) connects to the physical network. Tier-0 gatewayA Tier-0 gateway has downlink connections to Tier-1 gateways and uplink connections to physical networks. The Tier-0 gateway provides a gateway service between the logical and physical network. The Tier-0 gateway enables route redistribution, routing, and BGP, as well as optional T0 services. Tier-1 gatewayA Tier-1 gateway connects northbound to a Tier-0 gateway and to southbound segments. Tier-1 gateways may also provide centralized services such as load balancing, VPN services, NAT, DHCP, and so on.