Server And Application Migration Strategy — AWS Solutions Architect Pro (SAP-C02)
MGN Uses Continuous Replication; VM Import Needs Downtime
A fleet of production web servers must migrate to EC2 with a two-hour cutover window on Sunday night. AWS Application Migration Service installs an agent that continuously replicates block-level changes from live servers; the final sync-and-cutover takes minutes. VM Import/Export creates a point-in-time image and requires the source to be offline or quiesced during the entire import, which can take hours depending on disk size. For any production system that cannot sustain a multi-hour outage, MGN is the correct tool. VM Import applies when the source is already a powered-off virtual machine or the scenario explicitly permits extended downtime for the migration.
What This Pattern Tests
The exam describes a migration and tests strategy selection based on stated goals. Rehost (lift-and-shift) using Application Migration Service (MGN) moves servers as-is to EC2 — fastest, minimal risk, no operational improvement. Replatform moves to managed services with minimal changes — RDS instead of self-managed databases, Elastic Beanstalk instead of manual EC2 configuration. Refactor redesigns the application for cloud-native — containers on ECS/EKS, Lambda for event-driven, DynamoDB for NoSQL. The trap is choosing Rehost when the scenario says "reduce operational overhead" (that requires at least Replatform) or Refactor when it says "migrate within 2 weeks" (Refactor takes months).
Decision Axis
Migration priority determines strategy: speed = Rehost, quick operational wins = Replatform, long-term modernization = Refactor.
Associated Traps
More Top Traps on This Exam
Decision Rules
Whether SCT must precede DMS replication when the source and target database engines differ, making SCT a non-negotiable sequence step alongside MGN and DMS even when the cutover window constraint appears satisfied by replication continuity alone.
Whether AWS Application Migration Service alone satisfies both the application-server rehost and the Oracle-to-Aurora heterogeneous engine migration, or whether the Oracle tier requires a separate SCT-plus-DMS-CDC pathway alongside MGN for the application servers.
Domain Coverage
Difficulty Breakdown