Migrating applications and data to the Cloud is a complex process. You may want to distribute your applications to one or more Cloud services or move virtual machines, voluminous data or configurations to the Cloud or Clouds. You may want these Clouds to integrate and present a unified singular appearance to the end user. Each step will involve a number of complex sub-steps and each of these sub-steps will have to be executed with understanding and precision if your Cloud is to work efficiently for your enterprise.
Let us assume that the migration effort requires moving data and applications from a single unified local platform to a single unified Cloud service. The exercise must begin with taking stock. You need to determine exactly what you have and what you want to migrate to the Cloud. Will the data storage and application configurations work when your data is migrated to the Cloud? What are the changes you will have to make? Will these changes have to be cascaded? What kind of latency issues will you have to face? What kind of application and data tweaking you will have to do to ensure that your data and applications work just as well in the Cloud? Remember that relational databases use client-server architecture and you may have to move both the client and the server into the Cloud.
Moving forward, you may have to spend some time on network configuration issues. For instance, the use of domain name services will have to be examined in some detail. For instance, update of records, load balancers for distribution of workloads or addition of new servers with new IP addresses will have to be considered in depth. The challenges of moving VM images and migration of large databases will have to be addressed with an eye to the costs of the operation.
As Cloud services evolve, more complex arrangements are emerging. Businesses are also demanding a mix of services leading to the complexity. Multi-Cloud is just one example of such arrangements. Multi-Cloud migrations orchestrate public and private Clouds and use two or more public Infrastructure as a Service (IaaS) providers or two or more Platform as a Service (PaaS) providers to service the business need. The security systems may work from within a private Cloud or a public Cloud and facilitate private use based accounting to satisfy specific business needs and configurations.
As a result, various seemingly diverse technologies converge and integrate to meet exacting requirements while grappling with security and governance issues or associated resiliency issues. The integration then, drives complexity and the complexity needs to be managed with planning and vision.