How can I use the AWS load balancer?

In the context of AWS, here is the appropriate approach given:-

Creating the target group

First, you would need to create one or more target groups in the AWS management console. Every target group is associated with a specific protocol and port such as HTTP on port 80 or HTTPS on port 443.

Configuration of load balancer

Once you have created the target group then you can configure your AWS load balancer to use these target groups.

Routing traffic with rules

You can define rules on your load balancer to route the incoming traffic based on different criteria, such as URL path, and hostname.

Here is the AWS code snippet given which would create a target group, register an Instance with the target group, and create a routing rule for path-based routing:-

# Create Target Group

Aws elbv2 create-target-group 
  --name MyTargetGroup 
  --protocol HTTP 
  --port 80 
  --vpc-id vpc-12345678
# Register Target Instances with Target Group
Aws elbv2 register-targets 
  --target-group-arn arn:aws:elasticloadbalancing:us-west-2:123456789012:targetgroup/MyTargetGroup/abcdef123456 
  --targets Id=i-1234567890abcdef0 Id=i-0987654321fedcba0
# Create Routing Rule for Path-Based Routing
Aws elbv2 create-rule 
  --listener-arn arn:aws:elasticloadbalancing:us-west-2:123456789012:listener/app/my-load-balancer/1234567890abcdef/abcd1234 
  --priority 1 
  --conditions Field=path-pattern,Values=’/api/*’ 
  --actions Type=forward,TargetGroupArn=arn:aws:elasticloadbalancing:us-west-2:123456789012:targetgroup/MyApiTargetGroup/abcdef123456