An Application Load Balancer (ALB) is a managed service offered by Amazon Web Services (AWS) that provides load balancing functionality for applications running in the cloud. It is a layer 7 (application layer) load balancer that distributes incoming traffic based on rules that are defined by the user.
The ALB can distribute traffic to multiple targets such as Amazon EC2 instances, containers, and IP addresses, within and across multiple Availability Zones. It supports HTTP and HTTPS traffic and can route requests to different services based on the content of the request, such as the host header or the URL path.
Some key features of ALB include:
- Advanced routing: ALB provides advanced routing capabilities such as host-based routing, path-based routing, and redirecting to a different URL.
- Integrated with AWS services: ALB is integrated with other AWS services such as EC2, Auto Scaling, and Elastic Container Service (ECS) to provide a fully managed and highly available load balancing solution.
- SSL/TLS offloading: ALB can offload SSL/TLS termination from the backend servers, reducing the workload on the servers and improving performance.
- Health checks: ALB can perform health checks on the backend servers to ensure they are healthy and respond to requests. If a server fails a health check, the load balancer can stop sending traffic to it.
- Monitoring and logging: ALB provides metrics and logs that can be used for monitoring and troubleshooting the load balancer and the applications it serves.
ALB is a highly available and scalable service that can help improve the availability and performance of your applications in AWS.
