What Questions to ask before Migrating Apps to Public Cloud?


Public cloud hosting solution is an attractive option for many small to medium sized businesses because of three important factors and they are –

  • Pay-as-you-use
  • Speed
  • Scalability

However, not all applications are same and it has been seen that not all apps work best in a public cloud hosting platform. Keep in mind that there are some apps that don’t perform to their best of abilities in public cloud. In fact, some of them also cost more when hosting on cloud.

This simply means that you have to pre-judge whether migration of your apps to the platform of public infrastructure as a service will be of proper business value. To make such an assessment it is extremely important for you to judge the primary motivation for you to migrate to a cloud hosting solution. So, before you take the most important decision of migrating to a cloud, it is extremely important to get answers to 3 most important questions –

  • How to make choice of the apps for migration?
  • Which approach of migration is right for you?
  • What are the cloud migration tool options?

Now, let’s explore answer to these questions in more details –

How to make choice of the apps for migration?

As a first step you have to make proper assessment of the application and at the same time review the associated requirements. This needs to be done for compliance and well as performance. You have to do this in order to be a good candidate for public cloud.

You should check whether there is any specific need of the network as well as dependencies. Latency may become an issue until and unless system migration is done on the basis of the application’s dependencies (which may include latency, databases, and others).

Reviewing design of an application is very important before migrating the same to the cloud because those applications that are read and written on a regular manner to storage systems may cost more off premises. In case your app experiences significant spike in demand frequently and therefore experience fluctuating traffic are best fit for public cloud hosting. However, the applications that are more consistent and at the same time have predictable traffic outcome should remain in the in-house hosting solution. There is no need to migrate the apps from in-house hosting solution to a public cloud.

The assessment process becomes easier when the service provider of your cloud hosting solution offers tools for simplified assessment. Some of the examples of such tools include AWS (Amazon Web Services) Application Discovery Service as well as Azure Cloud Migration Assessment. It must be stressed here that pricing calculators are offered by biggest players in the cloud field such as Google Azure, and Amazon Web Services in estimating cloud costs.

It should be determined by you as a user whether the cloud provider meets the dual requirement of compliance as well as security. Also check out the location where data centres of the service provider are situated. Getting this information is important because you need to understand whether the service provider meets the strict standards of compliance. This becomes extremely important for businesses that have sensitive data to store.

Which approach of migration is right for you?

This is the second question for which you have to get an answer. Once you have decided upon the applications to be migrated, you (as a user) have to determine the approach or method that needs to be followed for migration.

There are two most common options available for migration and they are –

  • Rehost method (which is also called the “lift and shift” method)
  • Refractor method (which is also called the “rearchitect” method)

It has been seen that the first mentioned process above takes lesser time in migrating apps to cloud solution than that of the latter one. This is mainly because of the fact that the developers don’t get the chance of changing design or architecture of the application. In the rehost method, the migration is done as it is. Though this method is simpler method to put forward, it has been seen that there are many associated drawbacks. One such drawback is non-availability of access to autoscaling, one of the most important features of the cloud. Therefore, without any modification of the app, the user will not get any additional facility. However, the lift and shift method of migration is ideal for cloud disaster recovery. If a business has legacy apps then refactoring method is a better solution. However, this method is not only more costly but also time consuming.

What are the cloud migration tool options?

If there are large amount of data and applications that need to be moved by an enterprise then one of the viable migration would be the offline data migration. Here, the data is first stored in physical disks and then they are moved to a best cloud provider. It is more cost effective than a migration through network, utilising terabytes of data. Some of the popular offline data migration services include services such as Azure Import/Export, Google Transfer Appliance, AWS Snowmobile, and AWS Snowball. There are also 3rd party as well as native cloud provider tools available. While CloudVelox and Cloudyn are popular 3rd party tools, Microsoft Assessment and Planning Toolkit is a popular native cloud provider tool.