If your service provider enabled your organization virtual data centers for cross-virtual data center networking, organization administrators can create data center groups with multiple egress points and create stretched layer 2 networks among the participating virtual data centers.
Data center group
A group of up to four virtual data centers that are configured to share multiple egress points. A data center group can have one of the following egress points configurations:
Egress Points Configuration Type
Common egress points configuration
The data center group can be configured with one active egress point and one standby egress point. The two egress points are common to all participating virtual data centers across all network fault domains in the data center group.
Egress points configuration per fault domain
The data center group can be configured with one active egress point for each network fault domain in the data center group. Standby egresses cannot be created.
An organization can have multiple data center groups. An organization virtual data center can participate in multiple data center groups.
The participating organization virtual data centers can belong to different vCloud Director sites. See Configure and Manage Multisite Deployments.
Network Fault Domain
The network provider scope, typically representing the underlying vCenter Server instance with the associated NSX Manager.
An edge gateway that connects a data center group or network fault domain to the Internet. The edge gateway must belong to a virtual data center from the data center group. BGP routes are configured on the edge gateway representing the egress point and the universal router of the virtual data center group or network fault domain. Existing routes on the edge gateway are not affected.
A layer 2 network that is stretched across all virtual data centers in a data center group.