Changes to service endpoints for DynamoDB

[kellertk]

In AWS SDK for Java v2.28.4, we released changes to the DynamoDB client that adopt a new AWS account-based endpoints feature. For more information on account based endpoints, please refer to the official SDK documentation. In SDK releases from this version on, clients will connect to a DynamoDB endpoint in the form of (account-id).ddb.(region).amazonaws.com instead of dynamodb.(region).amazonaws.com.

If your network configuration blocks outgoing traffic to DynamoDB based on DNS names or endpoint URLs, you must adjust your configuration, because the service's DNS name will change. You may also choose to switch to an IP-based configuration. The IP address ranges for DynamoDB, as well as other AWS services, can be found in the AWS documentation.

You may instead disable account-based endpoints for DynamoDB by setting the config flag accountIdEndpointMode to disabled, as a system property or environment variable. We recommend against this because the DynamoDB service uses account-based endpoints to ensure performance and scalability.