Persistent BeanCreationException in ECS Fargate Containerized Java Application Despite Rollbacks and Image Changes

Hello everyone,

I'm seeking advice on a perplexing issue with our Java application hosted on AWS ECS Fargate, which spans across two containers. Recently, one of our containers began failing and ceased to work, presenting the following error:

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'dictionariesContainer' defined in class path resource [/ContainerFactory.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [DictionariesContainer]: Factory method 'dictionariesContainer' threw exception; nested exception is java.lang.RuntimeException: java.lang.Exception: Error occurred while getting dictionaries

This container is essential for our application, and it communicates over a VPN with on-premise services. Initially suspecting a recent change as the culprit, we attempted to rollback to a previous version of the application. Surprisingly, the error persisted across all previous versions we tried, indicating that the issue may not be directly related to the application code or Docker image updates.

Efforts to address the issue have included:

• Rolling back the application to several earlier versions.
• Deploying previous Docker images known to be stable.
• Verifying network and VPN configurations to ensure there's no connectivity issue affecting the container's ability to access required resources.

Despite these steps, the error remains unchanged, leaving the container inoperable and impacting our application's functionality. It's baffling that the error persists even when reverting to configurations and images that were previously stable and fully functional.

Questions for the community:

• Has anyone encountered a similar BeanCreationException that persists across different application versions and Docker images? If so, how was it resolved?
• Could external factors, such as changes in the network environment or AWS services, contribute to this issue? How might we diagnose and address such factors?
• Are there recommended strategies for troubleshooting container-specific issues on ECS Fargate, particularly those that might not be immediately apparent from application logs or errors?

Any insights, suggestions, or recommendations would be greatly appreciated. We're at a bit of a loss and keen to resolve this issue to restore our application's full functionality.