Which service logs would provide the MOST insight into how users are using a web application with EC2 instances behind a load balancer?

Elastic Load Balancing (ELB) access logs provide detailed insights into how users interact with a web application that is utilizing EC2 instances behind a load balancer. These logs capture information about each request sent to the load balancer, including the request's source IP address, request processing time, backend response time, and response codes. This information is vital for understanding traffic patterns, identifying performance bottlenecks, troubleshooting errors, and optimizing application performance.

The ELB access logs essentially serve as a complete record of the requests made to your load balancer, which can be analyzed to gain insights about user behavior, the types of requests being made, and how efficiently the EC2 instances are handling those requests. This logging is especially valuable for applications where high availability and traffic management are critical.

While other logging services such as Amazon S3 access logs and Amazon CloudWatch logs provide useful information for certain use cases, they do not specifically focus on user interaction with the application in the context of load-balanced traffic. Amazon S3 access logs track requests made to S3 buckets, and CloudWatch logs primarily monitor system performance and resource utilization rather than capturing detailed request-level data. AWS Lambda logs pertain to functions run in response to events, which is not applicable in