The preparation phase for an SAP-to-Azure migration follows a logical infrastructure-readiness path. First, a compatibility assessment (using tools like SAP Readiness Check) is mandatory to identify unsupported OS/DB versions or hardware requirements. Once the requirements are clear, the target environment must be established by deploying core networking components, such as Virtual Networks (VNets) and subnets, which form the "Landing Zone." Finally, an ExpressRoute connection is configured to provide the dedicated, high-bandwidth, low-latency link necessary for transferring large SAP databases and maintaining hybrid connectivity during and after the migration.

Microsoft Official Documentation: SAP on Azure migration guide - Preparation phase. This section details the necessity of assessing source system compatibility before infrastructure deployment.

Microsoft Cloud Adoption Framework (CAF): Azure landing zone for SAP. Explains that network topology (VNets/Subnets) must be deployed as a prerequisite to connectivity services like ExpressRoute.

SAP Support Note 1928533: SAP Applications on Azure: Supported Products and Azure VM types. This is the primary reference for the compatibility assessment step to ensure the target Azure environment supports the specific SAP landscape.

Microsoft Learn (AZ-120): Module: Plan for SAP on Azure - Networking and Connectivity. Specifies that ExpressRoute is the recommended connectivity solution for SAP migrations to ensure reliable data transfer.