Cloud migration has become a strategic priority for organizations seeking greater agility, scalability, and operational efficiency. However, while early planning discussions often focus on applications and compute resources, storage decisions are often deferred or simplified, even though they have a critical impact on performance, architecture, operational complexity, and cost.
Storage assessments should be carried out early, and be grounded in empirical data rather than assumptions, industry averages, or static inventories. A data-driven approach is essential to align workloads with the right requirements and the optimal cloud storage service for those requirements.
In this post, we explore the critical role of storage assessment, how it helps organizations understand their needs and select the enterprise storage service that best addresses them, and how Amazon FSx for NetApp ONTAP supports workloads running in the AWS Cloud.
What this post covers:
- The role and importance of storage assessment
- Common risks of inadequate storage assessment
- Best practices for conducting a comprehensive assessment
- FSx for ONTAP: Your storage foundation for migration and modernization
- Moving from storage assessment to well-architected execution with NetApp Workload Factory
- Closing thoughts
The role and importance of storage assessment
A storage assessment is an evaluation of an on-premises storage environment. It analyzes capacity utilization, data access methods, dependencies, performance characteristics, and workload variability across time—such as peak and cyclical usage patterns—to build a clear picture of storage behavior and requirements.
Different levels of storage assessment can be carried out:
- Light assessments are based solely on static configuration data. They might provide directional guidance; however, they rarely capture real workload behavior. As a result, storage selection and sizing decisions that are based on such an assessment might be inaccurate. Similarly, relying on industry averages or short, point-in-time data snapshots can often lead to overlooking important workload characteristics that directly influence performance and cost.
- Comprehensive assessments collect data over extended periods to capture daily and weekly usage cycles, peak workload behavior, and the impact of backup, replication, and maintenance operations. This depth of insight is essential when planning a migration to the AWS Cloud, where storage services must be precisely aligned with workload requirements.
The foundation of a successful cloud migration lies in a deep understanding of the data being moved. Organizations that invest in a full storage assessment are better positioned to rightsize their storage with actual workload requirements, avoid unnecessary overprovisioning, and reduce long-term costs. For this reason, initiating a comprehensive storage assessment should be a requirement—not an afterthought—when planning an AWS migration.
Common risks of inadequate storage assessment
The cost of skipping a storage assessment, or relying on a light version, is often realized only after data has been migrated, as operational issues emerge. These might include:
- Performance degradation
Without detailed workload data, storage throughput and bandwidth requirements are frequently underestimated. Workloads might be placed on storage tiers that can't sustain production-level demands. This risk is compounded by data gravity. Large, highly transactional datasets that aren't collocated with compute resources can introduce latency, network congestion, and degraded application response times that impact end users.
- Operational friction
Selecting storage without a full understanding of data service requirements—such as snapshots, replication, or multiprotocol access—can result in misalignment with existing operational practices. Teams are then forced to adjust workflows after migration, rather than modernizing at their own pace.
- Budget overruns
To mitigate uncertainty, storage is often overprovisioned during planning, leading to unnecessarily high costs. Alternatively, underprovisioning might result in the need for later changes and an unexpected increase in operational overhead.
- Limited flexibility
Storage architectures designed without visibility of workload variability and growth trends often struggle to support incremental scaling throughout the modernization journey, leading to costly rearchitecting later.
Best practices for conducting a comprehensive assessment
Amazon Web Services (AWS) offers several assessment options for workloads when migration is being considered, including AWS Transform, Migration Evaluator, and third-party solutions from certified vendors such as Matilda Cloud or Cloudamize.
The following are recommended best practices:
- AWS Optimization and Licensing Assessment (AWS OLA) is a complimentary, sensible first step in assessing and optimizing on-premises and existing cloud environments. It focuses primarily on compute utilization and licensing optimization (for example, Windows, SQL Server, and Oracle). The AWS OLA typically collects data through Migration Evaluator or third-party agents; however, it doesn’t include detached storage, which can represent up to 80% of on-premises storage capacity. As a result, it’s critical to complement an OLA with a full storage assessment.
- AWS Transform is an agentic AI-powered service designed to accelerate modernization. It expands assessment capabilities with storage analysis that includes detached storage across storage area network (SAN), network-attached storage (NAS), file servers, object storage, and virtual environments. This analysis provides detailed migration recommendations to AWS services such as Amazon Simple Storage Service (Amazon S3), Amazon Elastic Block Store (Amazon EBS), and Amazon FSx. At the time of writing, AWS Transform is available in select AWS regions.
- Third-party assessments, such as those from Matilda Cloud or Cloudamize, offer additional options for organizations seeking independent workload-aware analysis, provided they collect sufficient performance and capacity data over time.
As previously mentioned, a comprehensive storage assessment provides the foundation for making informed decisions about which AWS storage service can meet enterprise requirements over time. Without it, organizations risk choosing storage based on assumptions rather than observed workload behavior.
When assessment results are translated into design decisions, FSx for ONTAP emerges as a strong fit for enterprise workloads migrating to AWS.
FSx for ONTAP: Your storage foundation for migration and modernization
FSx for ONTAP is a fully managed AWS storage service built on NetApp® ONTAP® technology. It supports a wide range of workloads and provides capabilities that help organizations migrate efficiently, modernize data management, and simplify business continuity. FSx for ONTAP aligns with enterprise-grade storage management requirements by supporting consistent performance, integrated data resilience and protection capabilities, and multiprotocol access across Network File System (NFS), Server Message Block (SMB), and iSCSI.
Organizations already running ONTAP on premises can extend familiar operational models into AWS with FSx for ONTAP, reducing the learning curve and managing data consistently across hybrid environments. NetApp SnapMirror® technology replicates data from any ONTAP system—on premises or in the cloud—to FSx for ONTAP, including data that was left unsynchronized between initial transfer and cutover.
Beyond migration, FSx for ONTAP provides a storage foundation that supports the complete modernization journey. The same data layer can be used as workloads evolve—from Amazon Elastic Compute Cloud (EC2)-based applications to containerized environments such as Kubernetes—enabling data migration without changes to protocols or data access patterns. Combined with built-in storage efficiencies and scalable performance, this helps organizations to optimize costs and adapt their architecture over time, so that storage decisions made during the assessment continue to deliver value throughout the modernization journey.
Moving from storage assessment to well-architected execution with NetApp Workload Factory
To fully realize the value of a comprehensive storage assessment, organizations must translate its findings into architecture and planning decisions that align with AWS best practices. Storage assessments surface critical inputs—such as performance variability, capacity growth, availability requirements, and data protection needs—but without a structured framework, these insights can be difficult to apply consistently. Aligning planning decisions with the AWS Well-Architected Framework helps ensure that storage architectures are designed for reliability, performance efficiency, cost optimization, and operational excellence from the start.
NetApp Workload Factory helps operationalize assessment insights for Amazon FSx for NetApp ONTAP by embedding well-architected principles directly into workload planning and migration guidance.
Workload Factory assessment tools include:
- Total cost of ownership (TCO) calculators
Workload Factory has workload-specific TCO calculators that calculate potential cost savings when using FSx for ONTAP.
The following is an example of a cost-saving calculation for an Amazon Elastic VMware Service (EVS) workload running on FSx for ONTAP:
Learn more in our posts: Automatically calculate AWS storage savings with Workload Factory and Estimate Amazon EVS cost savings with FSx for ONTAP using the Workload Factory TCO calculator.
- Migration Advisor
After the migration decision is made, Workload Factory Migration Advisor wizards simplify and automate migration planning by using FSx for ONTAP to provide data-driven design for cloud deployment. You can also use the Migration Advisor to review the design, compare costs with alternative configurations, and automate the deployment of the recommended architecture according to best practices and vendor guidelines.
By grounding financial and technical decisions in data assessment and AWS Well-Architected guidance, organizations can move from planning to execution with predictable migration outcomes, greater confidence, and reduced risk.
The following deployment summary table provides an example of a detailed view of instance storage assignment:
- Deployment plan
At the end of the planning stage, Workload Factory presents the recommended deployment plan, including the configuration details and a cost comparison between the proposed FSx for ONTAP deployment and the same deployment on Amazon EBS, as seen in this example:
Closing thoughts
A storage assessment isn’t a technical formality—it’s a strategic business imperative. Organizations that complete a comprehensive storage assessment before migrating to the AWS Cloud can significantly reduce risk, improve cost efficiency, and achieve better long-term outcomes.
When storage design is grounded in real workload behavior rather than assumptions, infrastructure decisions become significantly more reliable. Consider evaluating FSx for ONTAP as part of your migration planning, using tools such as Migration Evaluator, AWS Transform, or Matilda Cloud to carry out a full storage assessment.
Starting with the right data is the first step toward a successful and sustainable cloud migration. Get started by completing the Migration Assessment request. Once in contact with the team, request a storage assessment or for an existing assessment contact your assigned AWS Solutions Architect.