7.4.2 External Networks
An external network in vCloud Director is a network providing external connectivity to organizations. Each external network is backed by one VLAN or VXLAN based port group on a virtual switch with uplinks to outside networks. This port group must be pre-provisioned before the external network can be created.
Note the following:
• Allow Overlapping External Networks must be enabled in vCloud Director settings to provision multiple VXLAN based external networks because they share the same transport VLAN.
• If the logical switch spans multiple vSphere Distributed Switch instances, it is backed by multiple port groups. The correct port group must be selected based on the needs (for example, compute cluster vSphere Distributed Switch port group).
External networks are used to provide Internet access, dedicated access to a direct connect type service, or access to shared services (syslog, OS licensing, patching).