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Cross-Region Transit Gateway Peering in AWS

Amazon Web Services (AWS) offers a global infrastructure that empowers organizations to deploy and scale their applications across different regions. One of the essential components for building a global network architecture is Transit Gateway, which simplifies the connectivity between various Amazon Virtual Private Clouds (VPCs) and on-premises networks. In this article, we'll explore how to establish peering between two Transit Gateways in different regions.

 AWS Transit Gateway - peering connection

Setting Up Cross-Region Transit Gateway Peering:

  1. Create Transit Gateways:
    Begin by creating Transit Gateways in the respective regions where you want to establish peering. Ensure that the necessary VPCs are attached to each Transit Gateway.

  2. Enable Peering:
    Navigate to the AWS Management Console and select the Transit Gateway service. From there, initiate the peering connection between the two Transit Gateways in different regions.

  3. Update Route Tables:
    Once the peering connection is established, update the route tables associated with the Transit Gateways to include routes for the remote VPCs. This step ensures that the Transit Gateways know how to route traffic to the interconnected regions.

  4. Security Groups and Network ACLs:
    Adjust Network Access Control Lists (ACLs) and Security Groups to permit traffic between the peered VPCs. Ensure that the necessary ports and protocols are open to facilitate communication between EC2 instances.

  5. Connectivity Testing:
    After configuring the necessary settings, perform connectivity testing to ensure that EC2 instances in different regions can communicate seamlessly. Use tools like ping or other application-specific tests to validate the connectivity.

If you are interested in the topic, you can see what it looks like in practice in my video tutorial:

Conclusion:

Cross-region Transit Gateway peering in AWS provides organizations with the ability to create a global network infrastructure that supports efficient and secure communication between resources deployed in different geographic locations. By following the outlined steps, businesses can establish peering connections between Transit Gateways in distinct regions and enable direct communication between EC2 instances, fostering a more robust and interconnected cloud environment. This capability is particularly valuable for enterprises with a global footprint, allowing them to build scalable and resilient architectures that meet the demands of a distributed and interconnected world.

Top comments (1)

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Howard Montes De Oca

I appreciate the very informative guide, but you should also mention to update the main route tables on the VPC in addition to the transit gateway route tables. Meaning transit gateway rt should be VPC CIDR -> peering and VPC rt should be peer CIDR -> transit gateway. This could be seen in the later portion of the video.