Study guide
Technical reference and lesson notes
Purpose of This Lesson
AWS provides specialized services for discovering on-premises environments, migrating servers and databases, transferring files, and tracking migration progress. The key exam skill is matching the migration requirement to the correct AWS service.
A typical migration environment may include:
- Physical servers
- VMware or Hyper-V virtual machines
- Relational databases
- Network-attached storage and file servers
- Existing connectivity through the internet, AWS Site-to-Site VPN, or AWS Direct Connect
AWS migration services address different layers of the environment rather than providing one universal migration mechanism.
Key Concepts
AWS Application Discovery Service
AWS Application Discovery Service collects information about on-premises servers and their utilization. The collected data helps assess the environment and plan migration waves, dependencies, and target sizing.
It can collect information such as:
- Host names
- IP addresses
- MAC addresses
- CPU utilization
- Memory utilization
- Disk information and utilization
- Network utilization
- Resource allocation details
Discovery data can be exported or stored in Amazon S3 for analysis with services such as Amazon Athena and Amazon QuickSight.
#### Discovery Connector
The Discovery Connector is designed for VMware environments. It is deployed as an OVA appliance and connected to VMware vCenter. This approach collects information about the virtualized environment without requiring an agent to be installed individually on every server.
#### Discovery Agent
The Discovery Agent is installed on individual servers. It can be used with physical servers and supported Windows or Linux systems, including servers running in VMware environments. Because it runs on the server, it can provide more detailed system and utilization information than a connector-only approach.
| Discovery method | Deployment model | Typical environment |
|---|---|---|
| Discovery Connector | OVA appliance connected to vCenter | VMware environments |
| Discovery Agent | Installed on each server | Physical servers, Windows, Linux, and VMware servers |
AWS Application Migration Service
AWS Application Migration Service is used to migrate servers into Amazon EC2. It is the appropriate service when the migration objective is to move workloads such as physical servers, VMware virtual machines, or Hyper-V virtual machines into AWS with minimal changes to the application.
Application Discovery Service helps determine what exists and how it is used. Application Migration Service performs the server migration itself. These services are complementary, not interchangeable.
AWS Database Migration Service
AWS Database Migration Service, commonly called AWS DMS, migrates databases to AWS database services such as Amazon RDS. It is intended for database migration rather than full-server migration.
Use AWS DMS when the primary migration object is a database and the target is a supported AWS database platform. A server migration tool is not the correct choice simply because the database currently runs on a server.
AWS DataSync
AWS DataSync is designed for moving file and object data between on-premises storage and AWS storage services. Relevant target services include:
- Amazon Elastic File System (Amazon EFS)
- Amazon S3
- Amazon FSx
DataSync is a data transfer service, not a general-purpose server migration service. It is a better fit for file shares, network-attached storage, and large-scale data movement than for migrating an entire operating system and its applications.
AWS Migration Hub
AWS Migration Hub provides a central place to monitor migration progress. It can track migrations that use AWS services as well as supported partner migration tools.
Migration Hub is primarily an orchestration and visibility layer. It does not replace Application Migration Service, AWS DMS, or DataSync as the service that performs the migration.
Architecture Decision Guide
| Requirement | Recommended service | Why |
|---|---|---|
| Inventory on-premises servers and collect utilization metrics | AWS Application Discovery Service | Provides server configuration, identity, and utilization data for assessment and planning |
| Discover VMware infrastructure through vCenter | Application Discovery Service Discovery Connector | Uses an OVA appliance connected to vCenter |
| Collect detailed information from individual Windows or Linux servers | Application Discovery Service Discovery Agent | Installs directly on each server |
| Move physical or virtual servers into Amazon EC2 | AWS Application Migration Service | Performs server-level migration to EC2 |
| Migrate a database to Amazon RDS or another supported database target | AWS Database Migration Service | Performs database-focused migration |
| Transfer files from on-premises storage to EFS, S3, or FSx | AWS DataSync | Optimized for managed data transfer |
| Monitor migration status across AWS and partner tools | AWS Migration Hub | Centralizes migration tracking and visibility |
| Analyze collected discovery data | Amazon S3 with Athena and/or QuickSight | Supports querying and visualization of discovery data |
Exam-Relevant Takeaways
- Application Discovery Service discovers; it does not migrate the workload.
- Application Migration Service migrates servers to EC2.
- AWS DMS migrates databases.
- AWS DataSync transfers file and object data.
- Migration Hub monitors migrations performed by AWS services and partner tools.
- The Discovery Connector is associated with VMware vCenter and is deployed as an OVA appliance.
- The Discovery Agent is installed per server and supports physical and supported Windows or Linux systems.
- Discovery information can be stored in Amazon S3 and analyzed using Athena or QuickSight.
- Existing connectivity to AWS may use the internet, Site-to-Site VPN, or Direct Connect, depending on the architecture and requirements.
Common Exam Traps
Confusing discovery with migration
Collecting CPU, memory, disk, and network information does not migrate a workload. Use Application Discovery Service for assessment and Application Migration Service for server migration.
Choosing DataSync for a complete server migration
DataSync transfers data. It does not reproduce an entire server operating system and application stack in EC2. For a server lift-and-shift migration, evaluate Application Migration Service.
Choosing AWS DMS for file shares
AWS DMS is database-focused. For NAS data, file shares, or large-scale file movement to S3, EFS, or FSx, evaluate DataSync.
Treating Migration Hub as the migration engine
Migration Hub provides centralized tracking. It does not itself perform server, database, or file migrations.
Selecting the wrong discovery method
The Discovery Connector is intended for VMware environments and connects to vCenter. The Discovery Agent is installed on individual servers and is the more appropriate option when discovering physical servers or obtaining host-level information from supported Windows and Linux systems.
Assuming every migration requires one tool
A single application may require several services: Discovery Service for inventory, Application Migration Service for servers, DMS for databases, DataSync for file data, and Migration Hub for centralized progress tracking.
Real-World Engineer Notes
- Begin with discovery before selecting migration tooling. Utilization and dependency information can prevent undersizing target EC2 instances or overlooking application relationships.
- Treat server, database, and file data migration as separate decisions. The original on-premises architecture may contain all three, but AWS provides different tools for each.
- Use the least invasive discovery method that provides sufficient information. A connector can simplify VMware-wide collection, while agents can provide more detailed host-level data.
- Plan network connectivity as part of the migration design. VPN, Direct Connect, or internet connectivity affects how migration components communicate and how data reaches AWS.
- Centralized visibility becomes increasingly valuable when multiple migration waves, AWS services, or partner tools are involved.
- Store discovery results in Amazon S3 when the organization needs repeatable analysis, historical comparison, SQL-style queries, or dashboards.
Quick Reference Summary
- Discover infrastructure: AWS Application Discovery Service
- VMware discovery appliance: Discovery Connector, deployed as an OVA and connected to vCenter
- Per-server discovery: Discovery Agent for supported physical, Windows, Linux, or VMware-hosted servers
- Migrate servers to EC2: AWS Application Migration Service
- Migrate databases: AWS Database Migration Service
- Transfer files and storage data: AWS DataSync
- Track migration progress: AWS Migration Hub
- Analyze discovery data: Amazon S3, Athena, and QuickSight
Flashcards
- Q: What is the primary purpose of AWS Application Discovery Service?
A: To collect inventory, configuration, and utilization information about on-premises servers and resources for migration assessment and planning.
- Q: Which Application Discovery Service component is used with VMware vCenter?
A: The Discovery Connector.
- Q: How is the Discovery Connector deployed?
A: As an OVA appliance connected to VMware vCenter.
- Q: When should the Discovery Agent be used?
A: When collecting information directly from individual supported servers, including physical servers and Windows or Linux systems.
- Q: Which service migrates servers into Amazon EC2?
A: AWS Application Migration Service.
- Q: Which AWS service is intended for database migration?
A: AWS Database Migration Service (AWS DMS).
- Q: Which service transfers data to Amazon S3, EFS, or FSx?
A: AWS DataSync.
- Q: What is the role of AWS Migration Hub?
A: It provides centralized monitoring and tracking for migrations performed by AWS services and partner tools.
- Q: Can Application Discovery Service migrate an application?
A: No. It discovers and reports infrastructure information; a separate migration service is required.
- Q: Which services can be used to analyze discovery data stored in Amazon S3?
A: Amazon Athena for querying and Amazon QuickSight for visualization and business intelligence.
Practice Questions
Question 1
A company wants to inventory its VMware environment and collect server names, IP addresses, resource allocation, and utilization data. The company wants to avoid installing software on every virtual machine. Which solution should it use?
A. Install the AWS Discovery Agent on every virtual machine
B. Deploy the AWS Application Discovery Service Discovery Connector and connect it to vCenter
C. Deploy AWS DataSync on the VMware cluster
D. Configure AWS Migration Hub without deploying discovery components
Correct answer: B
Explanation: The Discovery Connector is an OVA appliance designed for VMware environments and connects to vCenter. DataSync and Migration Hub do not provide this VMware inventory function, and the agent requires per-server installation.
Question 2
An enterprise must migrate several physical Windows servers and VMware virtual machines into Amazon EC2 with minimal application changes. Which AWS service is the best fit for the server migration?
A. AWS DataSync
B. AWS Database Migration Service
C. AWS Application Migration Service
D. AWS Migration Hub
Correct answer: C
Explanation: Application Migration Service is designed for migrating physical and virtual servers to EC2. DataSync transfers data, DMS migrates databases, and Migration Hub tracks migration progress.
Question 3
A company needs to transfer data from an on-premises network-attached storage system to Amazon EFS and Amazon S3. Which service should the architect recommend?
A. AWS Application Migration Service
B. AWS DataSync
C. AWS Application Discovery Service
D. AWS Migration Hub
Correct answer: B
Explanation: DataSync is designed for managed transfers of file and object data to AWS storage services such as EFS and S3.
Question 4
An organization is migrating databases to Amazon RDS and wants a central view of migration status across AWS migration services and third-party tools. Which combination best meets the requirements?
A. AWS DMS and AWS Migration Hub
B. AWS DataSync and Amazon QuickSight only
C. Application Migration Service and the Discovery Connector only
D. AWS Migration Hub and the Discovery Agent only
Correct answer: A
Explanation: AWS DMS performs the database migration, while Migration Hub provides centralized visibility across AWS and partner migration tools.
Question 5
A migration team wants to collect server utilization data, save the results for analysis, query the data with SQL, and create dashboards. Which combination should it use?
A. Application Discovery Service, Amazon S3, Amazon Athena, and Amazon QuickSight
B. AWS DMS, Amazon RDS, and AWS Migration Hub
C. DataSync, Amazon EFS, and Amazon EC2
D. Application Migration Service, Amazon S3, and AWS DMS
Correct answer: A
Explanation: Application Discovery Service collects the data. Amazon S3 can store it, Athena can query it, and QuickSight can visualize it.