Getting AWS Migration Right Starts With a Successful Plan
- janvier 21, 2021
There are many reasons to instigate a cloud migration — from greater scalability to enhanced cost control and more. However, we frequently see organizations thinking about moving to the cloud being ushered there quickly by a forcing function. And so it was for one of our clients, a leading supplier of energy solutions whose IT team faced a new corporate mandate to migrate its applications to the cloud and leave the datacenter — all within a firm timeframe.
When the manufacturer looked to find a partner to help create a plan to migrate to AWS, the IT team called on NTT DATA, who was already managing a portion of the company's application portfolio. Led by the CIO and Director of IT, they sought a trusted partner to help them navigate the waters of estimating a migration approach, timeline, and cost.
While the project's overarching goal was to migrate as many applications as possible within the company's portfolio to the AWS cloud as cost-effectively as possible, the first step in the process was to create a migration readiness plan.
Application inventory analysis
Using the customer's existing application inventory, we conducted a thorough interview process to:
- Categorize each application, both in-house and commercial apps, based on a "6R" analysis. This analysis examines each application for the best-fit migration strategy — whether to rehost, replatform, refactor, repurchase, retire or retain the application. (For a deeper dive, check out our Strategies for Large-Scale Cloud Migration planning guide.)
- Ascertain the business impact of each application, determining the number of people each application would impact.
- Analyze the business risk each application poses to revenue and/or operations.
Of the applications flagged for migration, we used these inputs to give each a 'shirt size' (e.g., small, medium, or large) that reflected the level of effort and time duration for a migration. We also determined any application dependencies at this stage so that we could migrate related applications simultaneously. Combining shirt sizes and dependencies allowed us to slot each application into a migration wave, categorized as low, medium, high and business-critical. By slotting application migrations into risk-adjusted waves, the teams maximize business continuity during the migration.
To ensure that we helped our client achieve its goal to migrate its applications as effectively as possible, we optimized our teams and infrastructure costs. For example, we created a standard team size with generic roles like Sysadmin, DBA, etc., for each combination of migration wave and migration approach — refactor, rehost, replatform, etc. For each role, we calculated a percentage of the team member's time that would be required given each migration's shirt size.
To ensure we managed costs optimally, we assigned a cost for each role. Using the team assignment and the migration wave along with the shirt size, we applied rate and time estimates to determine a people cost. We also estimated infrastructure costs by:
- Sizing the types of AWS and database instances the client would need, using data from TSO Logic and Cloud Chomp.
- Projecting future costs — out to five years — using instance size and preferred purchasing strategies. We calculated the projected costs using reserved instances for EC2 and databases, where available. Reserve Instances offer good savings, with users reporting up to 72% savings over on-demand pricing. Because Reserve Instances can be bought on a one- or three-year plan, we used a three-year plan to create our five-year projection.
In this first phase of the project, we helped the client achieve a detailed, risk-adjusted migration plan for each of its applications. Also, we set the client on the path to optimizing the human resources and infrastructure costs associated with its migration. NTT DATA consultants also taught the CIO's team along the way how to optimize company resources to help ensure that it reached its goal to migrate applications to the cloud within its firm deadline cost-effectively.
In this first phase, the NTT DATA team worked with the client to migrate a low-risk application as a proof of concept, helping the IT team learn what awaits them during the migration ahead. The company is building a strategic partnership with NTT DATA as it prepares for the work ahead, migrating additional applications with patterns based on the migration waves and AWS best practices the teams created.
Download our Strategies for Large-Scale Cloud Migration planning guide or read about NTT DATA's AWS migration practice.