Can Load Balancers Be Used Separately?

No, load balancers must be used together with other necessary components: listeners and backend server groups.

ELB automatically distributes incoming traffic across multiple backend servers based on the listening rules you configure. It expands the service capabilities of your applications and improves their availability by eliminating single points of failure (SPOFs). To use a load balancer to distribute traffic, you must add at least one listener to and associate backend servers (such as ECSs) with this load balancer.