Amazon Web Services Inc. (AWS), is a great option because it allows you to scale your workloads as needed.
AWS allows you to scale workloads. You can also use auto-scaling for limiting the number of workload instances you should have running. Auto-scaling can even detect unhealthy instances and automatically replace them.
As you might expect, scaling and load balancing is a function of the Amazon Elastic Compute Cloud (or EC2). You will need to open the EC2 console. Next, click the Load Balancers button in the navigation pane. Finally, click the Create Load Balancer button as shown in Figure 1.
[Click on the image to see a larger version.] Figure 1: Click on the Create Load Balancingr button. The console will now display the Define Load Balancer page. Figure 2 shows that you will need to give a name to your load balancer and also select an Amazon Virtual Private Cloud (or VPC) within which you want to create a load balancedr. As you go through the process of creating a load balancer, make sure that the Listener Configuration is set to HTTP. You may need to select subnets for your load balancer. This is only necessary if you use an advanced configuration or a non-default VPC.
[Click on the image to see a larger view.] Figure 2: This screen shows the basic load balancing configuration. You will see an option to create an intra-load balancer in the screen capture. Load balancers can be either internal-facing or Internet-facing. An Internet-facing loadbalancer has a public IP Address and a publicly resolvable name in DNS.
Click Next to select a security group that you want to assign to your load-balancer. While you must make an initial selection you can change it at any time.
Next, you will be taken the Configure Security Options screen. The contents of this screen will depend on the configuration options you originally entered. If you create an HTTP listener but no HTTPS listener, you will be prompted with a warning message advising you to return to the original step if you want to use SSL or HTTPS traffic with the loadbalancer.
After you have completed any security configuration settings, (or none), click Next to be taken to the Configure health Check screen. This screen allows you define what the workload should look like. To test whether the Web server responds to requests, you can do an HTTP ping on Port 80. You can also set threshold values, as shown in Figure 3. However, the default values will usually be acceptable.
[Click on the image to see a larger version.] Figure 3: How the load balancer checks the health of your Web site. Click Next to be taken to a screen asking you to add EC2 instances for the load balancer. This screen, as shown in Figure 4, shows all running EC2 instances. This screen capture shows one instance, but you might see multiple instances. Select the check boxes that correspond to the instances you wish to add the load balancer to.
[Click on the image to see a larger version.] Figure 4: Choose the instances that need to be load-balanced. This screen also includes check boxes that allow you to choose whether cross-zone load balance and connection draining should be turned on. You can also set the threshold time for connection draining. Both of these options will be enabled by default.
You will be taken to Add Tags screen. Tagging allows you to identify the load balancedr you are creating. This is particularly important
