AWS Database Migration Service (DMS) is a managed cloud service that enables you to migrate databases to AWS quickly and securely. The source database remains fully operational during the migration, minimizing downtime for applications that rely on the database.
Key features of AWS DMS include:
*…AWS Database Migration Service (DMS) is a managed cloud service that enables you to migrate databases to AWS quickly and securely. The source database remains fully operational during the migration, minimizing downtime for applications that rely on the database.
Key features of AWS DMS include:
**Supported Migration Types:**
- Homogeneous migrations (same database engine, e.g., Oracle to Oracle)
- Heterogeneous migrations (different database engines, e.g., Oracle to Amazon Aurora)
- On-premises to cloud migrations
- Cloud to cloud migrations
- Cloud to on-premises migrations
**Supported Database Sources and Targets:**
DMS supports major database platforms including Oracle, SQL Server, MySQL, PostgreSQL, Amazon Aurora, Amazon Redshift, Amazon DynamoDB, MongoDB, and more.
**Core Components:**
- **Replication Instance:** A managed EC2 instance that runs the migration tasks
- **Source and Target Endpoints:** Connection information for your databases
- **Migration Tasks:** Define what data to migrate and how
**Benefits:**
1. **Minimal Downtime:** Continuous data replication keeps source and target synchronized
2. **Cost-Effective:** Pay only for compute resources used during migration
3. **Reliability:** Automatic failover and self-healing capabilities
4. **Easy Setup:** Simple console-based configuration
5. **Supports CDC:** Change Data Capture ensures ongoing replication of changes
**Use Cases:**
- Database consolidation
- Disaster recovery setup
- Development and testing environments
- Database upgrades
- Moving to managed database services like Amazon RDS
**Integration with AWS Schema Conversion Tool (SCT):**
For heterogeneous migrations, AWS SCT helps convert database schemas and code to the target platform format before using DMS for data migration.
AWS DMS is a fundamental service for organizations looking to modernize their database infrastructure while maintaining business continuity throughout the migration process.
AWS Database Migration Service (DMS) - Complete Guide
Why AWS Database Migration Service is Important
AWS Database Migration Service (DMS) is a critical service for organizations moving their databases to the cloud or between different database platforms. In today's digital transformation era, businesses need to modernize their infrastructure while minimizing downtime and risk. DMS enables this by providing a managed, secure, and efficient way to migrate databases with minimal disruption to applications and users.
What is AWS Database Migration Service?
AWS DMS is a fully managed cloud service that helps you migrate databases to AWS quickly and securely. The source database remains fully operational during the migration, minimizing downtime to applications that rely on the database.
Key characteristics include: - Supports both homogeneous migrations (same database engine) and heterogeneous migrations (different database engines) - Can migrate to and from most widely used commercial and open-source databases - Supports one-time migrations and continuous data replication - Works with on-premises databases, Amazon RDS, Amazon Aurora, Amazon Redshift, Amazon S3, and more
How AWS DMS Works
AWS DMS operates through the following process:
1. Create a Replication Instance: This is an EC2 instance that runs the replication software. It connects to your source and target databases and moves data between them.
2. Define Source and Target Endpoints: Endpoints contain connection information for your source and target databases, including server name, port, and credentials.
3. Create a Migration Task: The task defines what data to migrate and how. You can migrate existing data, replicate ongoing changes, or both.
4. Migration Types: - Full Load: Migrates existing data from source to target - Change Data Capture (CDC): Captures and applies ongoing changes after full load - Full Load + CDC: Combines both for continuous replication
AWS Schema Conversion Tool (SCT)
For heterogeneous migrations, AWS provides the Schema Conversion Tool. SCT converts the source database schema and code to a format compatible with the target database. This is essential when migrating between different database engines like Oracle to PostgreSQL or SQL Server to MySQL.
Supported Database Engines
As Sources: Oracle, SQL Server, MySQL, MariaDB, PostgreSQL, MongoDB, SAP, IBM Db2, and more
As Targets: Amazon RDS, Amazon Aurora, Amazon Redshift, Amazon DynamoDB, Amazon S3, and the same engines listed above
Exam Tips: Answering Questions on AWS Database Migration Service
Tip 1: Remember that DMS is the go-to service for database migrations. If a question mentions moving databases to AWS with minimal downtime, DMS is likely the answer.
Tip 2: Understand the difference between homogeneous and heterogeneous migrations. Homogeneous uses the same engine (Oracle to Oracle), while heterogeneous uses different engines (Oracle to Aurora PostgreSQL).
Tip 3: For heterogeneous migrations, remember that AWS Schema Conversion Tool (SCT) is typically needed alongside DMS to convert the database schema.
Tip 4: DMS supports continuous replication using Change Data Capture (CDC). This is useful for scenarios requiring near-real-time data synchronization.
Tip 5: When questions mention migrating data warehouses to Amazon Redshift, DMS is a valid solution.
Tip 6: DMS can also migrate data to Amazon S3, making it useful for data lake scenarios.
Tip 7: The replication instance is the compute resource that performs the migration. Size it appropriately based on the migration workload.
Tip 8: DMS keeps the source database operational during migration, which is a key benefit for production environments requiring high availability.
Tip 9: If a question involves consolidating multiple databases into one, DMS supports this through multiple migration tasks pointing to the same target.