Software Engineering

How to Get a List of Available Regions from AWS CLI


AWS (Amazon Web Services) is a prominent cloud service provider that offers a wide range of services to businesses and individuals worldwide. One of the fundamental concepts in AWS is regions, which are distinct geographical locations hosting AWS infrastructure. Understanding regions is crucial for optimizing your cloud infrastructure’s performance, data residency, and compliance requirements. In this blog post, we’ll dive into the world of AWS regions, learn how to list available regions using the AWS CLI, and explore a handy command to fetch region details in a more reader-friendly format.

What are AWS Regions?

AWS Regions are physical locations worldwide where AWS has data centers to provide cloud services. Each AWS Region is designed to be completely isolated from other regions to achieve high availability and fault tolerance. AWS Regions are crucial for minimizing latency and ensuring compliance with data residency regulations. AWS currently offers multiple regions globally, allowing you to deploy your resources strategically for better user experiences and redundancy.

Listing AWS Regions with AWS CLI

The AWS CLI (Command Line Interface) is a powerful tool for interacting with various AWS services. To obtain a list of available AWS Regions using the AWS CLI, we use the ec2 describe-regions command. Here’s how you can do it:

aws ec2 describe-regions --query "Regions[].RegionName" --output table

Explanation:

  • aws ec2 describe-regions: The command used to fetch information about AWS regions.
  • --query "Regions[].RegionName": This parameter is used to filter the output and retrieve only the RegionName field from the response.
  • --output table: By specifying the output format as a table, the response is presented in a more readable and organized manner.

Sample Response:

When you execute the above command, you’ll receive a neat and informative table containing the list of AWS Regions and their respective names. Here’s a sample response you can expect:

---------------------------------
|          RegionName           |
---------------------------------
|         us-east-1             |
|         us-west-1             |
|         eu-west-1             |
|         ap-southeast-2        |
|         sa-east-1             |
|         cn-north-1            |
|         ap-northeast-1        |
|         eu-central-1          |
|         us-gov-west-1         |
---------------------------------

Advantages of `–output table“:

The --output table option serves several advantages for technical end-users:

  • a. Improved Readability: By formatting the output as a table, the region details are presented in a clear and organized manner, making it easy to read and understand.

  • b. Concise Information: The table format eliminates unnecessary details, providing users with only the necessary information they need.

  • c. Suitable for Scripts and Documentation: The tabular format is highly suitable for scripting purposes and can be easily incorporated into documentation or reports.

In Summary

Understanding AWS regions is essential for effectively utilizing cloud resources and optimizing your AWS infrastructure. Using the AWS CLI’s describe-regions command with the –output table option allows you to obtain a clear and concise list of available regions in a user-friendly format. Armed with this knowledge, you can strategically deploy your resources across AWS regions to achieve better performance, resilience, and compliance with regulatory requirements.