Security pillar primarily supports the earlier need to protect information, systems and assets using risk-aware controls because the security pillar addresses identities, detection, infrastructure and data protection, and incident response, but the new task is to spread work across additional independent resources; that is why Horizontal scaling is preferable here.

Right-sized architecture is intended to match provisioned resources to measured workload requirements because right sizing avoids both excess capacity and insufficient capacity for expected service levels; in this design the new outcome is to spread work across additional independent resources, which calls for Horizontal scaling rather than Right-sized architecture or the earlier Security pillar.

Performance efficiency pillar is intended to select and adapt resources to meet performance needs efficiently because performance efficiency includes choosing suitable technologies and maintaining efficient resource use as demand changes; in this design the new outcome is to spread work across additional independent resources, which calls for Horizontal scaling rather than Performance efficiency pillar or the earlier Security pillar.

AWS Database Migration Service (AWS DMS) primarily supports the earlier need to move or replicate database data to a supported target because AWS DMS supports migration and ongoing replication for suitable database engines, but the new task is to replicate source servers for a largely lift-and-shift migration; that is why AWS Application Migration Service is preferable here.

AWS Migration Hub is intended to track migration progress across applications and migration tools because migration Hub helps provide visibility across a portfolio's migration activity; in this design the new outcome is to replicate source servers for a largely lift-and-shift migration, which calls for AWS Application Migration Service rather than AWS Migration Hub or the earlier AWS Database Migration Service (AWS DMS).

AWS Schema Conversion Tool (AWS SCT) is intended to convert database schema and code for a heterogeneous database migration because AWS SCT helps transform schema objects and certain database code between supported engines; in this design the new outcome is to replicate source servers for a largely lift-and-shift migration, which calls for AWS Application Migration Service rather than AWS Schema Conversion Tool (AWS SCT) or the earlier AWS Database Migration Service (AWS DMS).

That description belongs to Capital expenditure (CapEx) because capEx involves purchasing owned assets such as servers and data-center equipment before the benefits are consumed; it is used to recognize upfront infrastructure purchase as a fixed investment, not to explain how Avoided data-center costs provides the function to reduce expenses for facility space, power, cooling and physical maintenance.

That description belongs to Cost visibility because cost reporting and allocation tools can reveal spend drivers that are less apparent in a shared data center; it is used to understand resource expenses before changing deployment decisions, not to explain how Avoided data-center costs provides the function to reduce expenses for facility space, power, cooling and physical maintenance.

That description belongs to Storage tier selection because different S3 storage classes trade storage charges against access and retrieval characteristics; it is used to reduce storage expense by matching access frequency to storage class, not to explain how Avoided data-center costs provides the function to reduce expenses for facility space, power, cooling and physical maintenance.

Elasticity is intended to increase and decrease capacity in response to changing demand because elasticity matches provisioned resources to workload demand, allowing capacity to contract after a spike; in this design the new outcome is to keep an application accessible despite the failure of an individual component, which calls for High availability rather than Elasticity or the earlier Resource pooling.

Resource pooling primarily supports the earlier need to benefit from provider-managed shared infrastructure without operating a dedicated facility because cloud providers abstract and share large infrastructure fleets while logically isolating customers, but the new task is to keep an application accessible despite the failure of an individual component; that is why High availability is preferable here.

Rapid global deployment is intended to make a proven application available in a newly targeted market quickly because cloud infrastructure in multiple geographic regions reduces the need to construct local facilities; in this design the new outcome is to keep an application accessible despite the failure of an individual component, which calls for High availability rather than Rapid global deployment or the earlier Resource pooling.

That description belongs to Automate recovery because automated detection and recovery reduce the time needed to handle predictable failure conditions; it is used to restore normal application behavior without waiting for routine manual intervention, not to explain how Continuous performance tuning provides the function to revisit resource choices as application demand evolves.

That description belongs to Vertical scaling because vertical scaling changes the size or power of one instance or server; it is used to increase the capacity of an existing compute resource, not to explain how Continuous performance tuning provides the function to revisit resource choices as application demand evolves.

That description belongs to Capacity awareness because good reliability planning accounts for capacity needs and service quotas; it is used to understand resource demand and quotas before workload demand exceeds limits, not to explain how Continuous performance tuning provides the function to revisit resource choices as application demand evolves.

Resource-efficient software primarily supports the earlier need to avoid unnecessary processing and storage when delivering the same output because reducing wasted computation contributes to performance and sustainability objectives, but the new task is to remove a single component whose outage would take down the whole system; that is why Avoid single points of failure is preferable here.

Operational excellence pillar is intended to improve how teams operate, monitor and continually refine workloads because operational excellence focuses on delivering business value through effective operations and continuous learning; in this design the new outcome is to remove a single component whose outage would take down the whole system, which calls for Avoid single points of failure rather than Operational excellence pillar or the earlier Resource-efficient software.

Infrastructure observability is intended to make system behavior visible through meaningful operational metrics and logs because useful telemetry helps teams detect performance changes and failures early; in this design the new outcome is to remove a single component whose outage would take down the whole system, which calls for Avoid single points of failure rather than Infrastructure observability or the earlier Resource-efficient software.

Capital expenditure (CapEx) is intended to recognize upfront infrastructure purchase as a fixed investment because capEx involves purchasing owned assets such as servers and data-center equipment before the benefits are consumed; in this design the new outcome is to save on flexible interruptible EC2 computing, which calls for Spot capacity economics rather than Capital expenditure (CapEx) or the earlier Cost visibility.

Cost visibility primarily supports the earlier need to understand resource expenses before changing deployment decisions because cost reporting and allocation tools can reveal spend drivers that are less apparent in a shared data center, but the new task is to save on flexible interruptible EC2 computing; that is why Spot capacity economics is preferable here.

Operating expenditure (OpEx) is intended to treat recurring service consumption as a running operational cost because opEx reflects spending as services and computing resources are consumed; in this design the new outcome is to save on flexible interruptible EC2 computing, which calls for Spot capacity economics rather than Operating expenditure (OpEx) or the earlier Cost visibility.

Fault tolerance primarily supports the earlier need to continue operating despite an individual infrastructure component failing because fault-tolerant systems absorb failures using redundancy, isolation and suitable application behavior, but the new task is to increase and decrease capacity in response to changing demand; that is why Elasticity is preferable here.

Scalability is intended to support larger workloads by adding capacity as requirements grow because scalability is the ability of a system to handle growth by increasing resources or distributing work; in this design the new outcome is to increase and decrease capacity in response to changing demand, which calls for Elasticity rather than Scalability or the earlier Fault tolerance.

Elastic test environments is intended to scale test capacity up for an evaluation then stop consuming it because temporary cloud test resources can be provisioned and removed with demand; in this design the new outcome is to increase and decrease capacity in response to changing demand, which calls for Elasticity rather than Elastic test environments or the earlier Fault tolerance.

That description belongs to Retire because retirement eliminates unneeded systems from the future estate; it is used to remove an application that no longer delivers sufficient business value, not to explain how Repurchase provides the function to replace an existing application with a different software product or SaaS solution.

That description belongs to Refactor or re-architect because refactoring changes design or code to gain capabilities such as managed services or elastic components; it is used to modify an application to exploit cloud-native capabilities more substantially, not to explain how Repurchase provides the function to replace an existing application with a different software product or SaaS solution.

That description belongs to Rehost (lift and shift) because rehosting relocates a workload while largely preserving its existing architecture; it is used to move an application to cloud infrastructure with minimal redesign, not to explain how Repurchase provides the function to replace an existing application with a different software product or SaaS solution.

That description belongs to Managed-service operational relief because managed services move specific tasks such as database engine patching to AWS; it is used to avoid administering an underlying platform for a common workload, not to explain how On-demand resource availability provides the function to obtain computing resources when a new workload is ready to launch.

That description belongs to Elasticity because elasticity matches provisioned resources to workload demand, allowing capacity to contract after a spike; it is used to increase and decrease capacity in response to changing demand, not to explain how On-demand resource availability provides the function to obtain computing resources when a new workload is ready to launch.

That description belongs to Agility because cloud agility shortens the time between a business idea and an available environment through on-demand provisioning; it is used to experiment and deploy new ideas without a long hardware procurement cycle, not to explain how On-demand resource availability provides the function to obtain computing resources when a new workload is ready to launch.

AWS CAF Operations perspective addresses a different objective, to prepare support, monitoring and service operations for migrated workloads, because the Operations perspective develops capabilities for operating workloads effectively; the checklist instead requires the distinct outcomes to manage transformation risks, priorities and portfolio decisions; modify an application to exploit cloud-native capabilities more substantially.

AWS Migration Hub addresses a different objective, to track migration progress across applications and migration tools, because migration Hub helps provide visibility across a portfolio's migration activity; the checklist instead requires the distinct outcomes to manage transformation risks, priorities and portfolio decisions; modify an application to exploit cloud-native capabilities more substantially.

AWS CAF Business perspective addresses a different objective, to connect cloud adoption to business outcomes and investment decisions, because the Business perspective aligns cloud initiatives with strategy, value and commercial priorities; the checklist instead requires the distinct outcomes to manage transformation risks, priorities and portfolio decisions; modify an application to exploit cloud-native capabilities more substantially.