To provide a fully routed network topology in a virtual data center, you can dedicate an external network to a specific NSX-T Data Center edge gateway.
In this configuration, there is a one-to-one relationship between the external network and the NSX-T Data Center edge gateway, and no other edge gateways can connect to the external network.
A tier-0 logical router or a VRF-lite gateway that is associated with a dedicated external network is part of the tenant networking stack. The external network is considered a part of the VMware Cloud Director network routing domain.
Dedicating an external network to an edge gateway provides tenants with additional edge gateway services, such as route advertisement management and border gateway protocol (BGP) configuration.
The tenant can decide which of the tenant networks that are attached to the edge gateway to advertise to the external network. This makes possible a mixture of NAT-routed and fully routed organization virtual data center networks.
You can dedicate an external network to an NSX-T Data Center edge gateway either during the edge gateway creation or later, by editing the edge gateway general settings.