Spring Boot Application deployed on Elastic Beanstalk Java environment returns 502

Question

I'm trying to deploy a very simple Spring Boot application on AWS Elastic Beanstalk using AWS's Java configuration (not their Tomcat configuration), but I keep getting a 502 error with the following log:

2016/06/10 02:00:14 [error] 4921#0: *1 connect() failed 
(111: Connection refused) while connecting to upstream, client: 38.94.153.178,   
server: , request: "GET /test HTTP/1.1", upstream:   "http://127.0.0.1:5000/test",
host: "my-single-instance-java-app.us-east-1.elasticbeanstalk.com"

I've tried setting my port via Spring's application.properties to what the log seems to want (5000, using server.port=5000) and have verified that my application runs successfully on that port on localhost.

This question is very similar, except that I'm deploying a JAR instead of a WAR. It seems like there is something I'm missing regarding configuring Nginx, and I don't know how to proceed.

Here's my Spring Application:

@SpringBootApplication
public class MyApplication {

    public static void main(String[] args) {
        SpringApplication.run(MyApplication.class, args);
    }

    @RestController
    public static class MainController {

        @RequestMapping("/test")
        public String testMethod() {
            return "Method success!";
        }
    }
}

Answer 1

Nginx doesn't know on which port your spring boot applicaiton is running. Make application run on port 5000 that Nginx redirects to by default by adding "server.port=5000" to application.properties or other suggested ways in the last step:

https://pragmaticintegrator.wordpress.com/2016/07/12/run-your-spring-boot-application-on-aws-using-elastic-beanstalk/

Answer 2

From your question description and the security group settings you send me your only inbound Port 80 for your EC2 instance was open to world through firewall and you were using port 5000 for your application. So using the security rule that I gave you it opened the inbound port 5000 too for your EC2 instance so your application started working without above error.