Microsoft’s Azure cloud service has soared to become the No. 2 cloud provider behind Amazon Web Services, and although Microsoft will tell you it’s because of the breadth of Azure’s offerings, an undeniable appeal of the service is that it makes migration from on-premises systems straightforward, from both Microsoft products as well as third-party products like Linux and open source databases.
Because Microsoft has had such a long and dominant position in the datacenter, its own Azure public cloud was designed to keep that dominance by being easy to migrate to for those Microsoft-based IT shops, such as by having the same services like Exchange available in both cloud and ion-premises versions. Such easy migration and dual cloud/on-premise services was an option Amazon Web Services and Google Cloud Platform simply couldn’t offer because they had no legacy systems.
Microsoft’s migration story breaks down into three major categories:
- Site
- App
- Database migration
Something to keep in mind: This guide describes the services available from Microsoft. There are also plenty of third-party tools, from major software vendors and small boutique shops alike, and hundreds of Microsoft MVPs and consultants who offer migration services.
There have been far too many horror stories from research reports detailing the nightmare companies went through because they did a migration on their own, believing they had the in-house skill to do it, only to realize in-house skills don’t automatically translate to the cloud, so they end up with an expensive mess. A third-party consultant should always be a consideration.
Site migration to Microsoft Azure
Any Azure migration starts with a free, basic discovery and assessment tool called Azure Migrate. Azure Migrate provides appliance-based, agentless discovery of your on-premises environments, from VMware-virtualized Windows and Linux VMs to applications and data. It provides an agent-based discovery for visualizing interdependencies among servers to identify multitier applications.
It also tells you if your on-premises app is suitable for migrating to an Azure VM, estimates the proper size of the Azure virtual environment for the app to properly function, and estimates the monthly costs of running it.
Another tool that you should consider using is the Microsoft Assessment and Planning Toolkit (MAP). MAP predates Azure but was designed to provide automated discovery and inventory of applications, application portfolios, and database readiness for Azure. It also estimates capacity needs for your applications and application dependencies.
For web apps, Microsoft provides additional migration tools. The Windows Site Migration Tool can migrate a site from as far back as Internet Information Server (IIS) Version 5 and Windows Server 2003, moving things like applications and virtual directories configured under each site, application pools, HTTP and HTTPS bindings, and databases used by the site. There is also the Linux Site Migration Tool for moving Apache-based sites to Azure.
Azure Migrate is also integrated with Azure Database Migration Service for database discovery and migration. As you would expect, it supports Microsoft SQL Server on-premises migration to the cloud, but Microsoft says it will support more popular database technologies in the future.
The third piece of the migration puzzle is Azure Site Recovery, which has two use cases:
- Migrate on-premises Windows Server and Linux apps and VMs to Azure.
- Use Azure for disaster recovery should your on-premises facilities go down (as detailed in InfoWorld’s Azure cloud services guide).
Azure Site Recovery does many types of replications, including:
- Azure VMs based in a primary region to a secondary region
- On-premises VMs and physical servers to Azure or a secondary on-premises datacenter
- Any workload running on supported Azure VMs, on-premises Hyper-V and VMware VMs, and Windows/Linux physical servers
Application migration to Microsoft Azure
Many major software vendors have made their apps available as services in Azure, as well as images of services. They include operating systems like Ubuntu Server, app servers like WebSphere, and apps like Informatica. They are in the App Marketplace, where you can try them for free. With such tools, you can migrate PaaS environments and things like Hadoop clusters from on-premises in just a few hours.
For server-based app migration, Microsoft offers two solutions: infrastructure as a service (IaaS) and platform as a service (PaaS). Both options support containers, which are being adopted rapidly by enterprises of all sizes. IaaS is more of a straight server migration: You move your app to Microsoft’s datacenter using a range of Windows Server and Linux operating environments of your choice.
Azure’s Hybrid Use Benefit, a feature found in the Azure Management Portal, lets Windows Server licensees use their on-premises Windows Server licenses in virtual machines on Azure for a savings of up to 40 percent on their Windows server licenses.
Database migration to Microsoft Azure
Azure Migrate is also integrated with Azure Database Migration Service for database discovery and migration. It supports migrating SQL Server 2005 or later databases to a single, pooled database, as well as managed instance environment in Azure SQL Database, which basically means one or more databases in a managed environment.
To ensure that the source database is compatible with Azure SQL Database, you use the Data Migration Assistant (DMA) to perform an assessment.
Databases and applications that rely on partially supported or unsupported functions might need to be re-engineered as part of the migration process. However, Microsoft says the SQL Database Managed Instance option provides nearly complete compatibility of instance-level features like DB Mail, CLR, and SQL Agent, making it easier to migrate SQL Server databases to Azure SQL Database.
To migrate a non-SQL Server database—such as Microsoft Access, Sybase, MySQL, Oracle, or IBM DB2—to Azure SQL Database, Microsoft offers the SQL Server Migration Assistant. If you have on-premises NoSQL, MySQL, or PostgreSQL databases, you can move to fully managed database services in Azure with Azure Cosmos DB, Azure Database for MySQL, and Azure Database for PostgreSQL, respectively.