Amazon Elastic Load Balancing Construct Library

---

AWS CDK v1 has reached End-of-Support on 2023-06-01. This package is no longer being updated, and users should migrate to AWS CDK v2.

For more information on how to migrate, see the Migrating to AWS CDK v2 guide.

---

The @aws-cdk/aws-elasticloadbalancing package provides constructs for configuring classic load balancers.

Configuring a Load Balancer

Load balancers send traffic to one or more AutoScalingGroups. Create a load balancer, set up listeners and a health check, and supply the fleet(s) you want to load balance to in the targets property.

# vpc: ec2.IVpc

# my_auto_scaling_group: autoscaling.AutoScalingGroup

lb = elb.LoadBalancer(self, "LB",
    vpc=vpc,
    internet_facing=True,
    health_check=elb.HealthCheck(
        port=80
    )
)
lb.add_target(my_auto_scaling_group)
lb.add_listener(
    external_port=80
)

The load balancer allows all connections by default. If you want to change that, pass the allowConnectionsFrom property while setting up the listener:

# my_security_group: ec2.SecurityGroup
# lb: elb.LoadBalancer

lb.add_listener(
    external_port=80,
    allow_connections_from=[my_security_group]
)