When you are responsible for migration of critical workloads to cloud, you must have a list of hardware or software systems that are the best candidates for targeting for the cloud environment. It is equally important to know the methods and techniques for moving those workloads to a cloud environment.

When considering the use of a cloud based infrastructure (to deliver either IT or business services) it is really important to consider how this will impact both new and established enterprises, especially those with existing IT investments.

Common patterns observed in cloud migration

• Traditional IT to Public Cloud
• Traditional IT to Private Cloud
• Traditional IT to Hosted Private Cloud
• Private Cloud to Public Cloud
• Private/Public Cloud to Hybrid Cloud
• Public Cloud to Private Cloud
• Public Cloud to Another Public Cloud

Choosing a pattern depends on your current system, desired flexibility, desired security and budget. For workloads which needs critical security and control, the natural choice is towards hybrid systems. For workloads which does not need high level security, but demands horizontal scaling, must be deployed on public cloud providing infrastructure at low cost and a mechanism to load balance the cluster.

Benefits of Public Multi-Cloud Deployment

• Users are not clustered near any single data center, but form clusters around multiple data centers or are widely distributed geographically.
• Regulations like GDPR limit options for storing data in specific data centers.
• Circumstances require that the public cloud be used in concert with on-premises resources.
• Applications can be configured resilient to the loss of a single data center.

Criteria to be considered during migration

• Minimal code changes to application and familiarity with platform.
• Granular control of resource usage and opportunity for auto-scaling.
• Lower cost although some limitations on feature availability.
• Replacing on-premise storage with cloud offerings.
• Integration with cloud utility services like SQS, SNS etc.
• Highly available service replacement using ELB, CDN etc.
• Better user experience, improved efficiency, and load leveling.

In all cases understanding the mechanisms for moving workloads to a cloud, addressing the governance model between cloud and non-cloud environments, and knowing which types of applications to migrate to the Cloud are key considerations. Chosen Cloud Migration Patterns can be the framework for categorizing those workloads for each use case.