How to Deploy an Application Load Balancer

Step 1: Visit the AWS Console and type “EC2” into the search bar. After selecting EC2 dashboard drop-down menu below, you will be select to the Elastic Load balancing, where you can click “Create Load balancer”. As shown in the screenshots.

Step 2: In this step, first you can launch EC2 instance, Amazon EC2 allows you to create virtual machines, or instances, that run on the AWS Cloud. Quickly get started by following the simple steps below.

In this step EC2 instance give name and tags for identification purpose specific name given to ec2 instance(Webserver).

Application and OS Images, An AMI is a template that contains the software configuration (operating system, application server, and applications) required to launch your instance. Search or Browse for AMIs if you don’t see what you are looking for below

After enter the all details , the EC2 instance created succesfully as shown below,

Step 3: Choose a load balancer type

Elastic Load Balancing supports different types of load balancers. In this step, we are going to create Application Load balancer, click on create an Application load balancer, and enter the basic configuration of application load balancer.

Step 4:Configure your load balancer

In this step to create an Application Load Balancer, you can provide basic configuration information for your load balancer, such as a name, scheme, and IP address type. Then, you provide information about your network, and one or more listeners. A listener is a process that checks for connection requests. It is configured with a protocol and a port for connections from clients to the load balancer.

Step 5: Configure your target group

you can create a target group, which is used in request routing. The default rule for your listener routes requests to the registered targets in this target group. The load balancer checks the health of targets in this target group using the health check settings defined for the target group.

• Choose Create target group.
• Under Basic configuration, keep the Target type as instance.
• For Target group name, enter a name for the new target group.
• Keep the default protocol (HTTP) and port (80).
• Select the VPC containing your instances. Keep the protocol version as HTTP1.
• For Health checks, keep the default settings.
• Choose Next.
• On the Register targets page, complete the following steps. This is an optional step for creating the load balancer. However, you must register this target if you want to test your load balancer and ensure that it is routing traffic to this target.

For Available instances, select one or more instances.

• Choose Create target group.
• Successfully created My-target-group.

Step 6:Test your load balancer

After you are notified that your load balancer was created successfully shows below.

Select the newly created load balancer.

Choose Description and copy the DNS name of the load balancer (for example,Test-LB-504127462.ap-south-1.elb.amazonaws.com). Paste the DNS name into the address field of an internet-connected web browser. If everything is working, the browser displays the default page of your server.

Step 7: Delete your load balancer

you are billed for each hour or partial hour that you keep it running. When you no longer need a load balancer, you can delete it. As soon as the load balancer is deleted, you stop incurring charges for it. Note that deleting a load balancer does not affect the targets registered with the load balancer. For example, your EC2 instances continue to run after deleting the load balancer created in this guide.

To delete your load balancer

• Open the Amazon EC2 console at https://console.aws.amazon.com/ec2/.
• In the navigation pane, under Load Balancing, choose Load Balancers.
• Select the checkbox for the load balancer, choose Actions, then choose Delete.
• When prompted for confirmation, choose Yes, Delete.

Conclusion

An Application Load Balancer supports HTTPS termination between the clients and the load balancer. Application Load Balancers also offer management of SSL certificates through AWS Identity and Access Management (IAM) and AWS Certificate Manager for pre-defined security policies. Cloud load balancing ensures distributing your site’s traffic to available servers effectively. It prevents downtime or machine breakdown issues while ensuring the applications are available to the client at all times.

Application Load balancer(ALB) – FAQ’s

Is the load balancer horizontally scalable?

Yes. The Application Load Balancer for VPC automatically adjusts its capacity based on the load. When horizontal scaling takes place, the number of IP addresses associated with the application load balancer’s DNS changes.

What are the default settings and allowed values for health check parameters?

Health check interval – Default is 5 seconds, and the range is 2 – 60 seconds.Health check response timeout – Default is 2 seconds, and the range is 1 – 59 seconds.Maximum retry attempts – Default is two retry attempts, and the range is 1-10 retries.

Are the ALB IP addresses fixed?

Application load balancer IP addresses are not guaranteed to be fixed. During system maintenance or horizontal scaling, you see changes in the available IPs associated with the FQDN of your load balancer.

Why does HTTPS listener creation or update tell me that my certificate is invalid?

Check for these possibilities:

• The provided certificate CRN might not be valid.
• The certificate instance in the Secrets Manager might not have an associated private key.

Why is my listener not receiving traffic?

Make sure that the security group rules that are attached to your load balancer allow incoming ingress and outgoing egress traffic on your listener’s port. Security groups attached to your load balancer can be found on your load balancer’s overview page. Locate the Attached security groups tab from the load balancer overview, then select the security groups that you want to view and modify their rules.

The application load balancer distributes incoming HTTP and HTTPS traffic across multiple targets such as Amazon EC2 Instances, microservices, and containers, based on request attributes. When the load balancer receives a connection request, it evaluates the Listener rules in priority order to determine which rule to apply, and if applicable, it selects the target from the target group for the rule action. AWS EC2 and Elastic Load Balancing are two different services that work well together. AWS ELB is built to support increased traffic without increasing the hourly cost. ELB scales automatically.