AWS VPC Communication: How to Pass Traffic Between Multiple VPCs

Passing Traffic Between Multiple VPCs: AWS Certified Advanced Networking - Specialty Exam Guide

Prev Question Next Question

Question

There are 3 VPC's that need instances to be able to pass traffic between each other.

How can this be achieved.

Answers

Explanations

Click on the arrows to vote for the correct answer

A. B. C. D.

Answer - C.

This is clearly given in the AWS documentation.

For more information on VPC Peering please refer to the below URL:

http://docs.aws.amazon.com/AmazonVPC/latest/UserGuide/vpc-peering.html
You have peered three VPCs together ina full mesh configuration. The VPCs are in the same AWS account and do not have overlapping CIDR blocks: * VPC Ais peered to VPC B through VPC peering connection pex-aaaabhbb * VPC Ais peered to VPC C through VPC peering connection pex-aasacces ‘© VPC Bis peered to VPC C through VPC peering connection pex-bbbbecee so00078 192.168.0078 pevcanaatns oxaanaccoe E160018 You may want to use this full mesh configuration when you have separate VPCs that need ta share resources with each other without restriction; for example, as a file sharing system. The route tables for each VPC point to the relevant VPC peering connection to access the entire CIDR block of the peer VPCs.

To enable communication between instances in different VPCs in AWS, you need to establish connectivity between them. There are several ways to do this, including using Virtual Private Network ( VPN) connections, AWS Direct Connect, and VPC peering.

In this scenario, the question specifically asks for instances to be able to pass traffic between each other across three different VPCs. Here are the possible ways to achieve this:

A. Peer the VPCs, transitive peering is now allowed in AWS: This option suggests that you should use VPC peering to connect the three VPCs. VPC peering enables you to connect two VPCs privately using AWS's network infrastructure, allowing you to route traffic between them as if they were on the same network. With transitive peering, you can establish connectivity between multiple VPCs using a single peering connection, which simplifies the network topology and reduces management overhead. You can also configure the routing tables to control the traffic flow between the VPCs.

B. Peer the VPCs and then Contact AWS support to enable transitive peering: This option is similar to option A but suggests that you need to contact AWS support to enable transitive peering. This option is incorrect because transitive peering is already allowed in AWS, and you don't need to contact support to enable it.

C. Peer the VPCs to each other in a full mesh configuration: This option suggests that you should establish multiple peering connections between the three VPCs to create a full mesh network topology. In a full mesh configuration, each VPC is directly connected to every other VPC, which enables instances in any VPC to communicate with instances in any other VPC. However, this approach can be complex to manage, especially if you have many VPCs.

D. Peer the VPCs, enable transitive peering via the route tables: This option suggests that you should establish peering connections between the three VPCs and then enable transitive peering by modifying the routing tables. While it is possible to enable transitive peering via the routing tables, this option oversimplifies the configuration process and does not provide enough detail to be a complete answer.

Therefore, the correct answer is A. Peer the VPCs, transitive peering is now allowed in AWS.

Prev Question Next Question