Connect Multiple AWS Accounts to a Central VPC for Identity Validation

Answer - B.

A VPC peering connection is a networking connection between two VPCs that enables you to route traffic between them using private IPv4 addresses or IPv6 addresses.

Instances in either VPC can communicate with each other as if they are within the same network.

You can create a VPC peering connection between your own VPCs, or with a VPC in another AWS account within a single region.

For more information on VPC Peering please see the below link:

<h2>Option B: Create a VPC peering connection with the central VPC</h2><p>This is the correct option for connecting multiple VPCs to a central VPC for identity validation. VPC peering allows communication between VPCs within the same AWS region, as long as they do not have overlapping IP ranges. With VPC peering, each VPC remains separate, and traffic is not routed through a central gateway.</p><p>To implement this solution, you need to create a VPC peering connection between each VPC and the central VPC. This requires the following steps:</p><ol><li><p>Determine the VPC CIDR ranges: Each VPC should have a unique CIDR range that does not overlap with the others or the central VPC.</p></li><li><p>Create a VPC peering connection: In the AWS Management Console, create a VPC peering connection between each VPC and the central VPC. This involves specifying the VPC IDs and CIDR ranges of the peered VPCs.</p></li><li><p>Accept the peering connection: Once the VPC peering connections have been created, they need to be accepted by the owners of each VPC.</p></li><li><p>Update routing tables: After the VPC peering connections are established and accepted, update the routing tables in each VPC to allow traffic to flow between the VPCs and the central VPC.</p></li><li><p>Configure security groups: Ensure that the appropriate security groups are in place to allow traffic to flow between the VPCs and the central VPC.</p></li></ol><h2>Option A: Migrate each VPC resources to the central VPC using migration tools</h2><p>This option involves moving all resources from each VPC to the central VPC. While it is possible to migrate resources using tools such as Import/Export, Snapshot, AMI Copy, and S3 sharing, it is generally not recommended for several reasons:</p><ol><li><p>Resource dependencies: Moving resources to a central VPC can introduce dependencies on other resources that are not in the same VPC.</p></li><li><p>Complexity: Migrating resources between VPCs can be a complex process, especially when dealing with large numbers of resources or complex dependencies.</p></li><li><p>Cost: Depending on the size and complexity of the resources being migrated, the cost of moving them to a central VPC can be significant.</p></li></ol><h2>Option C: Create a Direct Connect connection from each VPC endpoint to the central VPC</h2><p>Direct Connect is a service that allows you to establish a dedicated network connection between your datacenter and AWS. While it is possible to use Direct Connect to connect VPCs to a central VPC, it is not recommended for several reasons:</p><ol><li><p>Cost: Direct Connect can be expensive, especially if you are using it to connect multiple VPCs to a central VPC.</p></li><li><p>Complexity: Setting up and managing Direct Connect can be complex, especially if you are not familiar with networking.</p></li><li><p>Scalability: Direct Connect is designed for connecting datacenters to AWS, and may not be the best option for connecting multiple VPCs to a central VPC.</p></li></ol><h2>Option D: Create an OpenVPN instance in the central VPC and establish an IPSec tunnel between VPCs</h2><p>This option involves setting up an OpenVPN instance in the central VPC and establishing an IPSec tunnel between each VPC and the central VPC. While it is possible to use this approach to connect multiple VPCs to a central VPC, it is not recommended for several reasons:</p><ol><li><p>Complexity: Setting up and managing an OpenVPN instance can be complex, especially if you are not familiar with networking.</p></li><li><p>Scalability: While OpenVPN can be used to connect multiple VPCs to a central VPC, it may not be the best option for large-scale deployments.</p></li></ol><p>3</p>