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AWS Migration & Transfer

Migration Hub

Single dashboard to track the progress of application migrations to AWS

AWS Migration Hub provides a single dashboard to discover, plan, and track application migrations to AWS regardless of which migration tools are being used. It aggregates progress data from services like Application Migration Service, Database Migration Service, and third-party tools to give a unified view of where each application is in the migration journey. For cloud engineers, Migration Hub is the coordination layer for large-scale migrations involving dozens or hundreds of servers where tracking progress manually becomes unmanageable.

Key Concepts: Servers, Applications, and Migrations

Migration Hub organizes everything around three concepts: discovered servers (individual compute resources), applications (logical groups of servers), and migration tasks (the actual migration jobs running in connected tools).

ConceptDefinitionExample
ServerA discovered compute resource (physical or virtual)web-server-01, db-server-primary
ApplicationA user-defined group of servers that form one workload"E-commerce App" = web tier + app tier + database
Migration taskA replication or migration job from a connected toolMGN replication task, DMS migration task
Migration statusAggregated state of all tasks for an applicationNot started / In progress / Migrated
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Applications must be manually grouped in Migration Hub. Discovery tools like AWS Application Discovery Service (ADS) can identify server dependencies to help you group logically, but you confirm the grouping. Getting this right upfront saves significant tracking confusion during the actual migration.

Application Discovery Service Integration

Before tracking migrations, you need an inventory. AWS Application Discovery Service (ADS) feeds server and dependency data into Migration Hub via two discovery methods.

Discovery MethodHow It WorksData Collected
Agentless DiscoveryVMware vCenter connector scans VMs without installing agentsVM metadata, resource utilization (CPU/RAM/disk), no process data
Agent-based DiscoveryDiscovery agent installed on each serverRunning processes, network connections, inbound/outbound TCP connections, full dependency map

The dependency map from agent-based discovery is especially valuable - it shows which servers communicate with each other, helping you identify application boundaries and plan cutover sequencing (you must cut over dependent servers together).

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Discovery data is retained in Migration Hub for only 90 days after it was last updated. Export your discovery data to S3 via Athena integration before it expires, especially if your migration spans more than three months.

Connected Migration Tools and Status Tracking

Migration Hub aggregates progress from multiple migration tools. Each tool must be connected and the migration tasks must be associated with the correct servers in Migration Hub.

ToolIntegration TypeStatus Updates
AWS Application Migration Service (MGN)Native - automaticAutomatic progress updates per source server
AWS Database Migration Service (DMS)Native - automaticTask status and table-level progress
AWS Server Migration Service (SMS)Native (deprecated)Legacy - use MGN instead
CloudEndure MigrationNative (replaced by MGN)Legacy
Third-party toolsMigration Hub APICustom integration via API calls
bash
# Send a migration update from a custom tool via CLI
aws migrationhub notify-migration-task-state \
  --progress-update-stream "MyCustomMigrationStream" \
  --migration-task-name "server-42-to-ec2" \
  --task '{"Status":"IN_PROGRESS","StatusDetail":"Replication 45% complete","ProgressPercent":45}' \
  --update-date-time 2024-01-15T10:30:00Z

Migration Hub Strategy Recommendations

Migration Hub Strategy Recommendations analyzes your application portfolio and recommends the optimal migration strategy (the 7 Rs) for each server or application.

Strategy (7 Rs)DefinitionTooling
Rehost (Lift and Shift)Move as-is to EC2 with no changesAWS MGN
Replatform (Lift and Reshape)Move with minor optimizations (e.g., move to RDS)DMS + MGN
Repurchase (Drop and Shop)Move to SaaS (e.g., replace CRM with Salesforce)No AWS migration tool
Refactor/Re-architectRedesign to use cloud-native servicesNew development
RelocateMove VMware workloads to VMware Cloud on AWSVMware HCX
RetainKeep on-premises for nowNo migration
RetireDecommission the applicationNo migration
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Migration Hub Strategy Recommendations installs a collector on your on-premises environment and analyzes application dependencies, database compatibility (via DMS Fleet Advisor), and runtime behavior to suggest strategies. It is free to use and can save weeks of manual portfolio analysis.

Home Region Requirement

Migration Hub requires you to set a home region. All migration data is stored in this region and cannot be changed after it is set. This is a common gotcha that catches teams off guard.

ConsiderationDetail
Home regionMust be set before any discovery or migration data is sent to Migration Hub
Region lockCannot be changed once set - requires creating a new AWS account to change
Migration tool regionMGN and DMS can run in any region but they report to Migration Hub in the home region
Data residencyAll discovered server data and migration progress stored in home region only
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Set your Migration Hub home region before starting any discovery or migration. If you have data residency requirements (e.g., GDPR requiring EU storage), choose the home region carefully - you cannot move it later without losing all historical migration data.

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Interview Focus Points

  • 1What is AWS Migration Hub and how does it differ from AWS Application Discovery Service?
  • 2What are the 7 Rs of migration and how does Migration Hub Strategy Recommendations help categorize applications?
  • 3How do you group servers into applications in Migration Hub and why is this grouping important?
  • 4What is the Migration Hub home region and why can't it be changed after it is set?
  • 5How does Migration Hub integrate with MGN and DMS - is the integration manual or automatic?
  • 6How would you use Migration Hub to track a migration of 300 servers across a 6-month project?
  • 7What discovery method would you use to identify application dependencies before grouping servers for migration?