Java, Spring, AWS & Amazon's Elastic Beanstalk Tutorial

Java, Spring Boot, AWS & Amazon's Elastic Beanstalk: Common Deployment Pitfalls and How to Avoid Them

Amazon’s Elastic Beanstalk offers one of the easiest ways to deploy and manage Java applications on AWS. With support for Spring Boot, automatic scaling, load balancing, and managed EC2 instances, Beanstalk allows Java developers to focus on writing code rather than wrestling with infrastructure. However, deploying a Spring Boot application to Elastic Beanstalk isn’t always smooth sailing. Seemingly small oversights—like misused forward slashes in ZIP files or failing to expose port 5000—can derail your entire deployment.

Here’s a breakdown of what you need to know to deploy Java and Spring Boot applications successfully to Elastic Beanstalk, including critical but often overlooked details.

Why Elastic Beanstalk for Java and Spring?
Elastic Beanstalk is a Platform-as-a-Service (PaaS) offering from AWS that supports Java and Spring Boot out-of-the-box. It provides:

Automated environment provisioning

Built-in monitoring and logging via CloudWatch

Auto-scaling and load balancing

Easy integration with RDS, S3, and other AWS services

Spring Boot, with its embedded Tomcat server and opinionated defaults, pairs well with Beanstalk, making it possible to deploy with minimal configuration—when done correctly.

The Importance of Port 5000
One of the most common mistakes developers make is binding their Spring Boot app to the wrong port. By default, Spring Boot apps run on port 8080, but Elastic Beanstalk expects the application to respond on port 5000 for platforms like the Java SE environment.

If you fail to configure your app to listen on port 5000, Beanstalk's health checks will fail. This leads to red "Severe" health status and automatic restarts, which can be frustrating and confusing.

Solution: Set the port in your application by adding this environment variable:

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SERVER_PORT=5000
Or configure it in application.properties:

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server.port=5000
The Forward Slash ZIP File Issue
Elastic Beanstalk requires your application to be uploaded as a ZIP file—either directly or through the AWS CLI. But the format of that ZIP file matters more than many realize.

Problem: If you create your ZIP file on Windows using an archiving tool like Windows Explorer or WinRAR, it may use backslashes (\) instead of forward slashes (/) for internal paths. Beanstalk is a Linux-based system that expects forward slashes. When backslashes are used, deployment can fail silently or files may not be extracted correctly.

Solution: Always use a tool that ensures POSIX-compliant ZIP formatting. Use the zip command in a Unix-like environment (Mac, Linux, or WSL for Windows), or explicitly set the slash format if your tool supports it.

Other Common Deployment Issues
Incorrect JAR Packaging:

Elastic Beanstalk expects an executable JAR or WAR file in the root of the ZIP. If you nest it under a subdirectory, the app won’t start.

Wrong Environment Type:

Beanstalk has multiple Java environments—Java SE, Tomcat, Corretto. Choose Java SE for Spring Boot apps that bundle an embedded server, or Tomcat if you’re deploying a WAR and want Beanstalk to handle the servlet container.

Health Check Failures:

Beyond port issues, apps that take too long to start up or fail silently may be marked as unhealthy. Adjust healthcheck settings in .ebextensions or provide logs using eb logs.

Missing .ebextensions Config:

You may need to include a .ebextensions folder in your ZIP with custom configurations, like installing dependencies, setting environment variables, or updating the proxy server.

IAM Permission Errors:

The EC2 instance profile attached to your Beanstalk environment must have permissions to access resources like S3, RDS, or CloudWatch. If not, parts of your app may silently fail.

Best Practices for Smooth Deployments
Use CI/CD pipelines (like GitHub Actions or AWS CodePipeline) to build consistent ZIPs.

Include a Procfile if needed, specifying how your app should be launched.

Always test ZIPs in a sandbox environment before production deployment.

Set up custom log streaming so you can easily debug when the environment fails.

Java and Spring Boot provide a robust foundation for enterprise applications, and AWS Elastic Beanstalk takes the heavy lifting out of deployment. But small missteps—especially around port settings and ZIP formatting—can lead to frustrating errors. By paying close attention to port 5000 requirements, ensuring forward slashes in ZIP paths, and packaging your application properly, you can take full advantage of the automation and scalability that Beanstalk offers without stumbling over these avoidable pitfalls.

Видео Java, Spring, AWS & Amazon's Elastic Beanstalk Tutorial канала Cameron McKenzie