A Guide to Move Your Application to Amazon Cloud

Cloud Computing is the most hottest area of Information Technology today.  Companies that moved to Cloud Computing significantly reduced their costs, and they could concentrate on their core business. Once you are plugged into the cloud, you have access to thousands of new applications that can help your business, many of them free or low cost. You never have to buy servers again. You never have to worry about backups and disaster recovery. This article provides you essential guidelines to move your application to Amazon EC3 Cloud Computing.

• The first step should be to move the static content like  images, CSS, JavaScript files, etc to Amazon’s S3 storage.  It is essential to know that  Amazon S3 isn’t really a web server. It’s just a storage device that can be accessed over the web. You need to move the above static pages to Content Delivery Network  (CDN) to speed up page load times. It’s also best to give each file  future expiration header (so the browser doesn’t try to reload on each page view) and to gzip it.
• The deploy script has to smart enough so that it doesn’t reload the files that has not been changed on Cloud.
• You are advised to use separate sub-domains for content. The only difference for Javascript and Stylesheet is that  we need to serve gzip encoded versions to browsers that support it.
• The next major step is to move your Web Server and back end services like databases etc to Amazon EC2. It is not an easy task to move the databases. If you plan to keep your databases on RDBMS, you can use Amazon Elastic Block Store (EBS) that provides block level storage volumes for use with Amazon EC2 instances. Amazon EBS volumes are off-instance storage that persists independently from the life of an instance.
• You need to make a plan about how to take snapshots of your EBS and store them on S3 in order to do the back up.
• In case of failure of Amazon datacenters, you can make your infrastructure available for different zone while on cloud. For example, if your application is available on US and Europe cloud, in case of failure of US datacenter, Europe datacenter should be able to absorb the shock.
• You can use Amazon’s auto-scaling and Load Balancing  functionality to add or remove infrastructure that depends upon the load on your system. But, the caveat is that Amazon’s Load balancer does not support SSL.
• After you move all of the components of your application to Amazon Cloud, you have to find a better way to improve the service. You can try Amazon service SQS which allows front end applications to queue requests for other parts of the application  for asynchronous processing.
• Once you configure your apps on Amazon Web Server, you can start monitoring the service. Amazon  CloudWatch service is a nice tool to monitor your application.
• Since, S3 is ideal for storing large objects, it is advisable to lower your dependency on RDBMS. The popular convention is to move your data on SimpleDB because SimpleDB is ideal for small stubs of data.  But, SimpleDB has  limitation in terms of maximum size per row..