Azure Migrate

About Azure Migrate

Azure Migrate is Microsoft's migration planning and execution service for organizations moving servers, databases, web apps, virtual desktops, and other workloads to Azure. It provides a central place to discover existing environments, assess Azure readiness, estimate target costs, identify dependencies, build migration plans, and coordinate supported migration tools. The service is most useful before and during a cloud migration, when teams need evidence about what they run today and a practical path to the Azure services that can host those workloads.

What does Azure Migrate help organizations do?

Azure Migrate organizes migration work into discovery, assessment, planning, and execution. Teams can inventory servers and supported workloads, review configuration and performance information, group related systems, create assessments, estimate Azure resource costs, and track migration progress from an Azure Migrate project.

Microsoft currently supports planning for servers, databases, web apps, virtual desktops, and large-scale offline migration scenarios that can involve Azure Data Box. This makes Azure Migrate broader than a VM copy utility. It is intended to help teams decide where workloads should land and what needs to change before migration begins.

How does discovery work?

Microsoft recommends the Azure Migrate appliance for detailed and continuous discovery when the environment can connect to Azure. The appliance collects configuration metadata and performance data and can discover additional workload information such as SQL Server, web applications, PostgreSQL, MySQL, and MongoDB in supported scenarios.

For restricted or disconnected environments, Azure Migrate also supports collector-based or import-based discovery. These approaches are useful when a continuous appliance connection is not possible, but they can provide less continuous information than appliance-based discovery. Teams should choose the discovery method based on network constraints, workload type, and how much detail is needed for assessment.

What do Azure Migrate assessments show?

Assessments help determine whether discovered workloads are ready for Azure and what target configuration may fit them. Azure Migrate can create as-is assessments based on current configuration or performance-based assessments that use collected utilization data to recommend rightsized targets.

Assessment results can include readiness, recommended Azure targets, estimated Azure resource cost, and the migration tool Microsoft recommends for the workload. Because assessments are point-in-time outputs and performance data changes, buyers should treat them as planning evidence rather than permanent sizing decisions. Microsoft recommends allowing appliance-based discovery to collect enough performance history before relying on rightsizing recommendations.

Which workloads can Azure Migrate assess and migrate?

Current Microsoft documentation covers server migration from VMware, Hyper-V, physical servers, and supported virtual machines in other public clouds. Azure Migrate can also support assessment and migration planning for SQL databases, web applications, virtual desktops, and related application components.

The exact capabilities depend on the source environment and target service. For example, SQL assessments can recommend Azure SQL targets, while web app assessments can evaluate targets such as Azure App Service or Azure Kubernetes Service. Teams should check the current support matrix for their source operating systems, hypervisors, applications, databases, regions, and desired Azure destination before committing to a migration plan.

How does Azure Migrate pricing work?

Microsoft currently lists Azure Migrate and its core assessment tools at no additional charge, but migration projects can still create costs. Replication can consume Azure Storage, storage transactions, and data transfer. Microsoft currently states that Azure Migrate server migration is free for the first 180 days for each replicated machine, after which a monthly migration charge can apply if replication continues.

Third-party migration tools integrated into the Azure Migrate hub can have their own licensing fees. Related Azure services used during testing or after migration, such as virtual machines, databases, networking, backups, and monitoring, are billed separately. Buyers should therefore model the whole migration path instead of assuming that a free assessment means the migration project itself has no cost.

What should buyers know about the Azure Migrate appliance?

The appliance is a virtual machine deployed in the source environment for discovery and assessment. It runs services that collect configuration and performance metadata, maintain updates, discover supported databases and web apps, and in selected migration scenarios coordinate replication.

Microsoft publishes different setup guidance for VMware, Hyper-V, physical servers, and machines in other public clouds. The appliance needs appropriate permissions and network connectivity for the selected scenario. Teams should review security, proxy, firewall, credential, and data-residency requirements before deployment because the appliance sends collected metadata to the Azure Migrate project.

How is Azure Migrate different from Azure Site Recovery and Azure Backup?

Azure Migrate is the planning and migration hub. It helps discover workloads, assess readiness, estimate target cost, and coordinate migration execution. Azure Site Recovery is primarily a disaster-recovery service for replication, failover, and failback. Azure Backup is a protection and restore service for retained recovery points.

There can be technical overlap in replication concepts, but the buyer intent is different. Teams should use Azure Migrate for a planned move to Azure, Site Recovery when the primary goal is disaster recovery and business continuity, and Azure Backup when the requirement is backup retention and restore rather than workload relocation.

What are the main limitations and migration risks?

Azure Migrate does not remove the need for application testing, dependency validation, network planning, security review, identity design, or operational readiness. A technically successful server migration can still fail as a business migration if dependent systems, latency requirements, licensing, firewall rules, DNS, or data flows are missed.

Assessment limits also vary by workload and discovery method. Microsoft currently documents large project limits such as up to 35,000 servers for several assessment scenarios, while individual appliances have lower discovery limits. Older or unsupported operating systems can produce less reliable outcomes and may need upgrades before migration. Teams should also plan rollback, validation, cutover ownership, and post-migration cost monitoring before production changes.

Who should choose something else?

Organizations that only need ongoing disaster recovery should evaluate Azure Site Recovery instead of building a migration program around Azure Migrate. Teams that only need backup and restore should use Azure Backup. Small workloads that can be rebuilt directly as a managed Azure service may not need an extensive discovery project at all.

Azure Migrate is also not a replacement for application modernization design. If the real goal is to redesign applications around containers, serverless, managed databases, or a new data architecture, Azure Migrate can provide discovery and assessment evidence, but architecture teams still need to make the modernization decisions. Buyers should use Azure Migrate when a structured inventory, assessment, business case, dependency view, and coordinated migration path will reduce risk enough to justify the planning effort.