Elastic Beanstalk Change ELB Type

Amazon Elastic Beanstalk is a platform as a service (PaaS) offered by Amazon Web Services (AWS) that allows developers to rapidly deploy and manage applications in the cloud. One of its core components is the Elastic Load Balancer (ELB), which automatically distributes incoming application traffic across multiple targets, such as Amazon EC2 instances. Adjusting the ELB type in an Elastic Beanstalk environment can significantly affect application performance, scalability, and cost. In this article, we will explore how to change ELB types, the types available, and their respective applications.

Types of Elastic Load Balancers

AWS offers various types of load balancers, each to accommodate different needs and applications:

1. Classic Load Balancer (CLB)
   • Suitable for Amazon EC2 Classic networks.
   • Operates at both the request level (Layer 7) and connection level (Layer 4).
   • Primarily used for legacy applications and simple infrastructures.
2. Application Load Balancer (ALB)
   • Operates at the application level (Layer 7).
   • Ideal for modern HTTP/HTTPS-based applications.
   • Supports advanced routing, host-based routing, and path-based routing.
   • Recommended for microservices and container-based architectures.
3. Network Load Balancer (NLB)
   • Operates at the transport layer (Layer 4).
   • Designed for ultralow latency and high throughput.
   • Suitable for applications that require extreme performance, like gaming and real-time trading platforms.
4. Gateway Load Balancer (GLB)
   • Operates at Layer 3.
   • Integrates with virtual appliances, such as firewall and intrusion detection systems.
   • Used for advanced network traffic inspection and analysis.

Changing ELB Type in Elastic Beanstalk

Changing the ELB type is a straightforward process but requires careful planning to avoid disruptions in service. The following steps outline how you can change the ELB type in your Elastic Beanstalk environment.

1. Evaluate Requirements:
   • Assess your current application needs.
   • Determine the benefits you can attain from another ELB type.
   • Consider compatibility with your existing infrastructure.
2. Environment Configuration:
   • Access the AWS Management Console.
   • Navigate to Elastic Beanstalk and select the environment you wish to modify.
   • Choose the option to Modify Load Balancer.
3. Update ELB Type:
   • Specify the desired ELB type.
   • Ensure that your application security group and VPC settings accommodate the new ELB type.
4. Deploy Changes:
   • Apply configuration changes.
   • Monitor the deployment process and verify that instances are healthy under the new load balancer.
5. Testing and Validation:
   • Perform load and integration testing.
   • Validate that all application functionalities are working as expected.
   • Monitor performance metrics and get customer feedback.

Example Scenario

Consider a scenario where a web application initially uses a Classic Load Balancer (CLB). The application evolves to require modern application features such as path-based routing and better SSL support. Transitioning to an Application Load Balancer (ALB) allows the deployment team to implement these features:

• Ref: SubnetA
• Ref: SubnetB