What is Azure Database Migration Service?
Azure Database Migration Service (DMS) is a fully managed service for migrating SQL Server databases to Azure. The current service specifically covers modernization toward Azure SQL Database, Azure SQL Managed Instance, and SQL Server on Azure VMs, supporting both offline and online migrations with minimal downtime.
Core Features
- Offline migration to Azure SQL Database, plus offline and online migration to Azure SQL Managed Instance and SQL Server on Azure VMs
- Schema migration from source to target
- Migration progress tracking via an optional tracking resource
- Managed through the Azure portal, PowerShell, or Azure CLI
- Uses the same underlying assessment technology as the Azure Arc readiness assessment to prepare for migration
Typical Use Cases
- Modernizing on-premises SQL Server environments to Azure SQL Database or Managed Instance
- Lift-and-shift of SQL Server to Azure VMs with minimal downtime
- Preparation and assessment ahead of a larger database migration
Benefits
- Minimal downtime with online migration for business-critical workloads
- Free Standard tier for straightforward offline migrations
- Integrates with automation via PowerShell and Azure CLI
- Support for private endpoints to securely connect source and target
Integration with innFactory
As a Microsoft Solutions Partner, innFactory supports you with database migration to Azure: selecting the right migration tool, assessment, execution, and post-migration optimization.
Frequently Asked Questions
What is Azure Database Migration Service?
Azure Database Migration Service (DMS) is a managed service for migrating SQL Server databases to Azure targets such as Azure SQL Database, Azure SQL Managed Instance, or SQL Server on Azure VMs, with minimal downtime for online migrations.
Which databases are supported?
The current DMS service is focused on modernizing SQL Server to Azure SQL targets. For other source and target databases, Microsoft offers complementary migration tools and assessments; the right solution should be evaluated per project.
What is the difference between offline and online migration?
With offline migration, the source is unavailable during the migration. With online migration, continuous replication runs with minimal cutover downtime, suitable for workloads with high availability requirements.
What does the service cost?
The Standard tier for offline migrations is free. The Premium tier for online migrations is billed on a usage basis per vCore-hour; refer to the official pricing page for current terms.
Note: All product information on this page has been compiled with care, but is provided without guarantee and may be outdated or incomplete. Cloud services evolve rapidly — features, pricing, SLAs, and availability change frequently. Authoritative and up-to-date information can only be found on the official product page of Azure (official documentation). This page does not represent an offer by Azure.
