How to Creating a Network Load Balancer in AWS

Define Your Load Balancer

First, provide some basic configuration information for your load balancer, such as a name, a network, and a listener.

A listener is a process that checks for connection requests. It is configured with a protocol and port for the frontend (client to load balancer) connections, and a protocol and port for the backend (load balancer to backend instance) connections. In this example, you configure an Internet-facing load balancer in the selected network with a listener that receives TCP traffic on port 80.

To define your load balancer

1. Open the Amazon EC2 console at https://console.aws.amazon.com/ec2/.
2. From the navigation bar, select a region for your load balancer. Be sure to select the same region that you selected for your Amazon ECS container instances.
3. In the navigation pane, under LOAD BALANCING, choose Load Balancers.
4. Choose Create Load Balancer.
5. On the Select load balancer type page, choose Create under Network Load Balancer.
6. Complete the Configure Load Balancer page as follows:
   1. For Name, type a name for your load balancer.
   2. For Scheme, choose either internet-facing or internal. An internet-facing load balancer routes requests from clients over the internet to targets. An internal load balancer routes requests to targets using private IP addresses.
   3. For Listeners, the default is a listener that accepts TCP traffic on port 80. You can keep the default listener settings, modify the protocol or port of the listener, or choose Add listener to add another listener.
      Note

      If you plan on routing traffic to more than one target group, see ListenerRules for details on how to add host or path-based rules.
   4. For Availability Zones, select the VPC that you used for your Amazon EC2 instances. For each Availability Zone that you used to launch your Amazon EC2 instances, select an Availability Zone and then select the public subnet for that Availability Zone. To associate an Elastic IP address with the subnet, select it from Elastic IP.
   5. Choose Next: Configure Routing.

Configure Routing

You register targets, such as Amazon EC2 instances, with a target group. The target group that you configure in this step is used as the target group in the listener rule, which forwards requests to the target group. For more information, see Target Groups for Your Network Load Balancers.

To configure your target group

1. For Target group, keep the default, New target group.
2. For Name, type a name for the target group.
3. Set Protocol and Port as needed.
4. For Target type, choose whether to register your targets with an instance ID or an IP address.
   Important

   If your service's task definition uses the awsvpc network mode (which is required for the Fargate launch type), you must choose ip as the target type, notinstance. This is because tasks that use the awsvpc network mode are associated with an elastic network interface, not an Amazon EC2 instance.

   You cannot register instances by instance ID if they have the following instance types: C1, CC1, CC2, CG1, CG2, CR1, G1, G2, HI1, HS1, M1, M2, M3, and T1. You can register instances of these types by IP address.
5. For Health checks, keep the default health check settings.
6. Choose Next: Register Targets.

Register Targets with the Target Group

Your load balancer distributes traffic between the targets that are registered to its target groups. When you associate a target group to an Amazon ECS service, Amazon ECS automatically registers and deregisters containers with your target group. Because Amazon ECS handles target registration, you do not add targets to your target group at this time.

To skip target registration

1. In the Registered instances section, ensure that no instances are selected for registration.
2. Choose Next: Review to go to the next page in the wizard.

Review and Create

Review your load balancer and target group configuration and choose Create to create your load balancer.

Create an Amazon ECS Service

After your load balancer and target group are created, you can specify the target group in a service definition when you create a service. When each task for your service is started, the container and port combination specified in the service definition is registered with your target group and traffic is routed from the load balancer to that container.