The administrator should click on theblue box representing the logical link between the two Tier-0 Gateways.

In the multi-tenant architecture ofVMware Cloud Foundation (VCF) 9.0, networking is structured hierarchically with VPC Gateways, Transit Gateways, and Tier-0 Gateways. Under normal conditions, traffic between isolated divisions (such as Division A and Division B) that need to communicate might be routed "North" all the way to thePhysical L3 Devices(the physical core routers) before being routed back down. However, if these physical devices are oversubscribed or reaching their throughput limits, this creates a performance bottleneck.

To optimize this flow, NSX allows forRoute Leakingat the Tier-0 layer. By establishing a logical peering or connection directly between twoTier-0 Gatewayswithin the virtual fabric, administrators can exchange routing information (prefixes) between the two environments without the traffic ever leaving the SDDC.

To control exactly which networks are shared and to prevent routing loops or unauthorized access,Route-Mapsmust be applied at this inter-gateway connection point. These route-maps define the "Permit" or "Deny" statements for specific IP prefixes being "leaked" from one routing table to another. By clicking the highlighted link between the Tier-0 Gateways, the administrator is targeting the specific control plane interface where these prefix exchanges occur. This configuration ensures that East-West traffic between Division A and Division B is handled locally by theNSX Edge Nodes, effectively bypassing the oversubscribed physical L3 devices and significantly reducing latency and physical network congestion.