What should a solutions architect do to meet these requirements?
Set up inter-Region VPC peering between the VPC in us-east-1 and the VPCs in eu-west-2.
Create private virtual interfaces from the Direct Connect connection in us-east-1 to the VPCs in eu-west-2.
Establish VPN appliances in a fully meshed VPN network hosted by Amazon EC2. Use AWS VPN CloudHub to send and receive data between the data centers and each VPC.
Connect the existing Direct Connect connection to a Direct Connect gateway. Route traffic from the virtual private gateways of the VPCs in each Region to the Direct Connect gateway.
Explanations:
Inter-Region VPC peering allows direct communication between VPCs in different regions, but it does not facilitate connectivity between on-premises data centers and the VPCs. Additionally, peering cannot be established directly between VPCs in different regions via Direct Connect, which is necessary for this scenario.
Creating private virtual interfaces from the Direct Connect connection in us-east-1 to the VPCs in eu-west-2 would not work because Direct Connect virtual interfaces can only connect to VPCs in the same region as the Direct Connect connection. This option does not provide the required connectivity between the two regions and the data centers.
Establishing VPN appliances in a fully meshed VPN network would introduce significant operational overhead due to the complexity of managing multiple VPN connections. This solution does not scale well and is not the most efficient way to connect data centers with multiple VPCs across regions.
Connecting the existing Direct Connect connection to a Direct Connect gateway allows routing traffic between VPCs in different regions via their virtual private gateways. This solution scales well and reduces operational overhead by centralizing management of the Direct Connect connection while enabling connectivity between the data centers and VPCs across regions.
As I see it, the answer is:
Connect the existing Direct Connect connection to a Direct Connect gateway. Route traffic from the virtual private gateways of the VPCs in each Region to the Direct Connect gateway.