Yes, you can add multiple endpoint groups to a single listener in AWS Global Accelerator. Here are the detailed points explaining this capability:
- In AWS Global Accelerator, a listener is configured to process inbound connections from clients based on specified ports (or port ranges) and protocols (TCP, UDP, or both). Each listener can have one or more endpoint groups associated with it[13].
- An endpoint group is a collection of endpoints (such as Network Load Balancers, Application Load Balancers, EC2 instances, or Elastic IP addresses) in a specific AWS Region. Each endpoint group is tied to exactly one listener but a listener can have multiple endpoint groups, each typically representing a different AWS Region[6][9][13].
- When you add endpoint groups to a listener, you specify the AWS Regions where you want to direct traffic. Global Accelerator then routes incoming traffic to the optimal endpoints within these groups based on health checks and traffic policies[6][13].
- You can add multiple endpoint groups to a single listener via the AWS Management Console, AWS CLI, or API. In the console, after selecting a listener, you choose "Add endpoint group" and specify the region and other settings. You can repeat this to add additional endpoint groups for the same listener[6].
- This design allows Global Accelerator to distribute traffic across multiple regions under a single listener, improving availability and performance for global applications[13].
- For custom routing accelerators, each listener can also have multiple endpoint groups, one per AWS Region where you have VPC subnet endpoints. This is similar to standard accelerators but tailored for routing to EC2 instances in VPC subnets[12].
- However, an AWS Region can have only one endpoint group per listener. So, while a listener can have multiple endpoint groups, they must be in different AWS Regions[8].
In summary, a single listener in AWS Global Accelerator can have multiple endpoint groups associated with it, each representing a different AWS Region, allowing you to route traffic globally and flexibly across your application endpoints. This is a core feature of Global Accelerator's design to optimize traffic distribution and high availability[6][9][13].
Citations:
[1] https://docs.aws.amazon.com/global-accelerator/latest/dg/about-endpoint-groups.html
[2] https://docs.aws.amazon.com/global-accelerator/latest/dg/about-listeners.html
[3] https://docs.aws.amazon.com/global-accelerator/latest/dg/about-custom-routing-endpoint-groups.html
[4] https://docs.aws.amazon.com/global-accelerator/latest/dg/about-endpoints.html
[5] https://www.nops.io/glossary/what-is-aws-global-accelerator/
[6] https://docs.aws.amazon.com/global-accelerator/latest/dg/about-endpoint-groups.create-endpoint-group.html
[7] https://docs.aws.amazon.com/global-accelerator/latest/dg/about-listeners.creating-listeners.html
[8] https://boto3.amazonaws.com/v1/documentation/api/1.16.27/reference/services/globalaccelerator.html
[9] https://awscli.amazonaws.com/v2/documentation/api/latest/reference/globalaccelerator/list-endpoint-groups.html
[10] https://docs.aws.amazon.com/global-accelerator/latest/dg/about-endpoints-adding-endpoints.html
[11] https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-resource-globalaccelerator-listener.html
[12] https://docs.aws.amazon.com/global-accelerator/latest/dg/about-custom-routing-listeners.html
[13] https://boto3.amazonaws.com/v1/documentation/api/1.21.9/reference/services/globalaccelerator.html
[14] https://awscli.amazonaws.com/v2/documentation/api/latest/reference/globalaccelerator/create-listener.html