Memory hook: Latency, throughput, durability, support.
Must remember
- Choose managed disk tiers and file services from the SAP workload’s supported IOPS, throughput and latency requirements. Database data, logs, shared directories and backups can have different needs.
- Disk striping can aggregate performance where supported; simple volumes reduce complexity. Validate limits at both disk and VM levels rather than adding disk IOPS beyond the host’s throughput cap.
- Caching settings and Write Accelerator are workload- and disk-specific. Follow supported SAP/HANA guidance, especially for write-sensitive database logs; a faster benchmark with unsafe caching is not acceptable.
- Azure NetApp Files and Azure Files can supply supported shared-storage scenarios. Plan protocol, permissions, throughput/capacity, snapshots, networking and regional availability.
- Encrypt data with appropriate platform or customer-managed keys and protect access. Key unavailability can become an application outage, so permissions and recovery belong in the storage design.
- Backups and snapshots must be application-consistent where required. Coordinate database state and test restores instead of assuming a storage snapshot is always a valid SAP recovery point.
Choose under exam pressure
| Requirement | Choice and reason |
|---|---|
| Need shared SAP directories | A supported Azure Files/NetApp Files design with required availability and permissions. |
| Database log latency is high | Inspect supported disk/caching/Write Accelerator configuration and VM limits. |
Traps
- More disks cannot bypass every VM-level throughput ceiling.
- A crash-consistent snapshot may not meet the required application recovery semantics.
Active recall
1. Why separate data and log requirements?
Their access patterns, latency sensitivity and supported caching settings differ.
2. What constrains a striped volume?
Individual disks, aggregate design and the VM’s overall storage limits.
3. Why test snapshot restoration?
To verify consistency, required dependencies and actual recovery time.
4. What does storage encryption not replace?
Access controls, backup policy and application authorization.
5. How choose a file service?
By supported SAP scenario, protocol, performance, availability and operational requirements.