Many organizations are moving workloads to the public cloud, and Amazon Web Services (AWS) is a primary option. Read on to understand key cloud migration concepts, options for migrating to AWS, pricing and costs you can expect after your migration, and automated tools that can help you plan and execute your migration.
What is Cloud Migration?
Cloud migration involves moving information systems, applications or data to a cloud computing environment. Three common cloud migration models are:
- Moving workloads from an on-premises data center to the public cloud
- Moving workloads from one public cloud provider to another (cloud to cloud migration)
- Reverse cloud migration, also known as repatriation, which involves moving workloads from a public cloud back to a local data center
The overall goal or benefit of a cloud migration is to host applications and data in the most effective IT environment possible, optimizing factors like cost, performance, and security. Many organizations migrate on-premises applications and data to public cloud infrastructure to take advantage of improved resiliency, self-service, redundancy, and flexible pay-as-you-go models.
AWS Cloud Migration Strategy
If you are migrating an application or portfolio of applications to AWS, here are key considerations for building your strategy.
Migration Preparation and Goals
Get a clear understanding of the current situation, the architecture of your existing applications, the challenges you face and your business goals. Define goals and set up a business case for the AWS migration. Possible goals could include:
- Reducing costs
- Easier scalability
- Improving resilience and availability
Based on your goals, decide which applications should be migrated to Amazon.
Discovery and Migration Planning
Explore your IT product portfolio and consider the migration strategy to use for each application. Common strategies are:
- Lift and shift – move applications to the cloud as-is
- Refactor – rebuild applications to suit cloud infrastructure
- Replatform – use an existing cloud-based service to replace the current application
Each application can use a different migration strategy. Map out your entire portfolio and decide which applications should be migrated, and to what extent.
Designing, Migrating, and Validating Applications
Based on your selected strategy, create a detailed migration plan for each application. To understand how your migration strategy and tools actually behave in your environment, start with a few applications as a proof of concept. Then, with the support of your organization’s
stakeholders, proceed to execute a complete migration plan.
Operations
When the application moves to the cloud, it runs within AWS and the on-premise version of the application is retired (unless you are using a hybrid model). Closely monitor applications and collect feedback from users and stakeholders, to see how successful your first AWS applications are. Learn from the feedback and use it to fine tune migration processes for the next applications.
AWS Pricing Models Overview
Costs are a central consideration in any migration project. In many cases, a key motivation for migration is cost savings. Therefore, before migrating to AWS, you should understand AWS pricing models, decide which one to apply to each application, and use the AWS cost calculator or other tools to estimate your actual expected costs.
On-Demand Pricing
The default AWS pricing model is called on demand pricing. Amazon resources are billed per hour or per second depending on actual usage. On-demand pricing is flexible, but it is also the most expensive option. Many organizations start with on-demand pricing as they adapt to the cloud environment and understand their requirements, and later move to a different model.
The major advantage of on-demand pricing is that it converts costs to operating expenses (OpEx) without any upfront investments or time commitments. It is most suitable for mission-critical applications or workloads with unexpected load peaks.
On-Demand Pricing with Enterprise Discount Program (EDP)
Organizations can apply for long-term on-demand rates with Amazon EDP. To use EDP, you must purchase enterprise support and commit to a certain level of spending within a specified amount of time. You will receive a predetermined discount depending on your spending commitment, and you can and should negotiate to get a bigger discount.
For example, you can improve your bargaining power by planning and optimizing your workloads ahead of time, and consolidating accounts between different departments or business units to show more spend.
EDP is suitable for organizations with a large cloud budget and well-known, predictable infrastructure requirements. An organization may have several applications with irregular workloads, but which combined, have a predictable total capacity.
Reserved Instances
On Amazon, you can reserve instances for 1 to 3 years and receive up to 75% off the price. However, if at some point during the term you need to scale down, you cannot delete a Reserved Instance. This reduces flexibility, but you can still benefit from advanced automation options and service ecosystem offered by Amazon.
The reserved instance model is mainly suitable for running large enterprise applications in the cloud, with predictable usage or pre-planned growth.
Spot Instances
AWS spot instances offer the biggest discount, with up to 90% off the price of on-demand compute instances. Spot Instances let you bid on spare computing power on Amazon’s open market. Prices change every 5 minutes. If your bid is higher than the current market price, you will receive a spot instance of the instance type you select, in a specific Amazon availability zone.
Spot instances can be tricky to work with, because Amazon may suspend an instance if capacity is unavailable, or if the current Spot price exceeds your maximum bid, with only 2 minutes notice.
Spot instances are suitable for organizations with advanced cloud-native development capabilities and the ability to dynamically cluster, start, stop, and migrate applications. Also highly suitable to stateless and highly distributed batch processing applications.
AWS Migration Assessment Tools
Vendor-provided migration tools, which in the case of AWS are provided at no extra cost, are extremely helpful in executing a successful migration. Here are tools Amazon provides that can help you plan and optimize your cloud migration.
Migration Evaluator
Migration Evaluator provides accurate data-driven recommendations to select the right size and cost for cloud deployments. Its predictive analytics provide insights about environments, price changes and deployment options, ensuring each workload is running in the configuration with the lowest possible total cost of ownership (TCO). The tool can help you establish a
clear business case for accelerating your migration plan.
Cloud Adoption Readiness Tool (CART)
AWS Cloud Adoption Readiness Tool (CART) is a survey-based solution that checks your organization’s readiness for migrating to AWS. The surveys are broken into six categories:
- Business – whether business goals are aligned with the cloud
- People – skill sets and cultural enablers for cloud migration
- Process – IT and business processes that could benefit from cloud migration
- Platform – existing technological and IT systems
- Operations – operational processes that could impact migration
- Security – security and compliance requirements for applications and datasets
After completing the CART survey, you can download a customized Cloud Migration Assessment, which charts your readiness and suggests next steps. CART reports include maps, charts, and scores that can help you assess your current state of readiness and understand how to improve your readiness score.
AWS Migration Hub
Migration Hub helps you track and monitor AWS migration projects, regardless of which tools or approaches you are using to perform migration. It provides metrics and migration progress visibility for entire application portfolios, as they are gradually migrated to the cloud. The tool can also provide recommendations for right-sizing AWS resources for on-premise workloads.
Conclusion
In this article I reviewed the basic concepts and strategies of AWS migration. I discussed AWS pricing options such as on-demand pricing, reserved instances and spot instances, and automated tools offered by AWS at not cost which can help speed your migration:
- Migration Evaluator
- Cloud Adoption Readiness Tool
- AWS Migration Hub
I hope this will be helpful in making your migration to the Amazon cloud a success.