If you are currently running an On-premise version of SQL Server, and looking to migrate to the cloud, what are your options? The answer, as any good consultant will tell you, depends.
Are you looking to take advantage of built-in high availability, built-in disaster recovery, reduce operating costs, remove administration overhead, or modernize your data estate? Whilst not an exhaustive list, these are some of the most common migration motivations.
Before we dive into the options available within Azure in 2022, let’s take a high-level look at patterns commonly used as the framework when forming a migration strategy.
In general, there are four broad patterns: rehost, refactor, rearchitect, or rebuild. Companies may use a mix and blend of the patterns, however it’s important to ensure that whatever pattern/s used, should be dependent on your business goals and motivations.
With these patterns in mind, let’s look at Azure SQL and what options are available. There are three main options as outlined below. The three options in conjunction with a migration pattern, will inform your strategy for migrating your On-premise SQL Server to the cloud.
The following is a breakdown of each option, touching lightly on where each fit within a migration pattern.
SQL Server on Azure Virtual Machines
This option may suffice if you require migration of your on-premises SQL Server databases and applications without any database change, ongoing operating system-level access, the ability to deploy application or services on the host where SQL Server lives, full administrative rights over a dedicated SQL Server instance, or as a starting point within a rehost migration pattern.
Azure SQL Managed Instance
This option may be suitable if your current SQL instance relies on cross database queries, or you require Instance-level objects across databases, including logins, credentials, SQL Agent jobs etc. SQL Managed Instance has near 100% compatibility with the latest SQL Server (Enterprise Edition) database engine. With the operational benefits of Platform-as-a-Service (PaaS), such as automatic patching, version updates, automated backups, and high availability, you can focus solely on managing the instance while Azure manages the infrastructure.
This option fits within the rehost or refactor migration pattern and may suit a company looking for the benefits of PaaS, that has investments within SSRS or SSIS.
Azure SQL Database
A relational database-as-a-service (DBaaS) hosted in Azure that falls into the category of Platform-as-a-Service (PaaS). This option fits within a rearchitect or rebuild migration pattern. Azure SQL offers support for modern cloud applications on a managed database service, that includes serverless compute. This service can often be use when building out smaller data warehouses or as a landing zone for relational data, used further downstream in a visualization layer like Power BI.
An import aid in building out your migration strategy is the offering known as Azure Hybrid Benefit. Azure Hybrid Benefit is a licensing offer that helps you to significantly reduce the costs of running your workloads in the cloud. This allows an organization to use On-premise Software Assurance-enabled Windows Server and SQL Server licenses within Azure, unlocking savings based on your prior investments.
As outlined above, downstream from your business goals and motivations, a migration strategy will consider the 3 Azure SQL options available, assessing based on functionality and how each option lines up within a particular migration pattern. Companies often employ a migration pattern as step one within a long-term plan to eventually rearchitecting or rebuild a given solution. This allows the journey to the cloud to start, ensuring a long-term view exists to utilize all the benefits that Azure and the cloud has to offer.
