Designing and Implementing SAP Infrastructure on Azure
Core building blocks
Infrastructure design centers on virtual networks, subnets, network security groups, and routing. Separate subnets for application, database, and management tiers; use user-defined routes or Azure Firewall for egress control and to avoid asymmetric routing with ExpressRoute. Storage selection is a frequent exam topic: Premium SSD or Ultra Disk for database volumes, Azure NetApp Files for shared file systems and scale-out HANA, and standard storage only for non-critical data. Disk caching rules matter - read-only caching for OS disks, none for database log volumes.
Sizing and configuration traps
Questions often present a VM size that is valid generally but not SAP-certified, or a storage layout that violates the certified configuration (for example, placing HANA log and data on the same disk or misusing write accelerator). Another trap is the SAP-specific Azure extension and the SAP solution configuration: the Azure VM agent and the SAP monitoring extension must be installed for support. Also watch for availability set versus availability zone confusion, and for Accelerated Networking being disabled by default on older images. Remember that HANA scale-out requires Azure NetApp Files or specific certified storage, not ordinary managed disks.
Worked example
For a production S/4HANA system, choose an M-series VM, place /hana/data and /hana/log on separate Premium SSD or Ultra Disk volumes, /hana/shared on Azure NetApp Files, and disable caching on log disks. Rule of thumb: if a proposed disk layout cannot be mapped to a certified SAP Note, treat the design as wrong regardless of performance claims.