We are planning to migrate our on-premises environment to Azure. The current setup includes 10 file servers, 15 SQL servers, and about 70 application servers. We have a production subscription and are deciding whether to create a separate development/test subscription for the SQL and application workloads, since those environments are not production. Our initial approach is lift-and-shift migration. We also have approximately 50 TB of archive files that only need to be accessed occasionally. What subscription structure and Azure storage approach would you recommend, and are there migration considerations we should address before moving everything as virtual machines?
4 Answers
For the 50 TB archive, Azure Blob Storage is generally much cheaper than keeping the data on actively managed file shares. Put infrequently accessed data in a cool or archive tier, and use lifecycle policies to move blobs between tiers automatically. The archive tier has retrieval delays and access charges, so it is best only when the data is rarely needed. If users need a familiar mounted share or frequent access, Azure Files may be more appropriate but will usually cost more.
A separate development/test subscription is usually worth considering, especially if you can use development licensing benefits. However, check the limitations carefully: these subscriptions may have different SLA and access requirements, and licensing benefits can depend on your agreement type and how the resources are provisioned. Keep production isolated with its own subscription, management groups, policies, and budgets.
Lift-and-shift can be a practical first phase, particularly if hardware is due for replacement or you need to move quickly, but it is rarely the most cost-effective long-term design. Assess the application and web tiers first; some of those workloads may be better candidates for platform services, managed databases, or containers. At minimum, plan a second phase for right-sizing VMs, optimizing SQL, and gradually modernizing the applications.
Before migrating, build a proper landing zone and review the cloud adoption and well-architected guidance. Inventory dependencies, network connectivity, bandwidth, downtime tolerance, identity, backup, disaster recovery, security, and cost controls. A Microsoft partner or experienced migration consultant may also be able to help with funding programs and an assessment, but the design should be based on your workload requirements rather than simply copying every server into Azure.
That approach also avoids creating a large collection of expensive VMs that later has to be redesigned. A migration assessment should identify which systems can move as-is and which ones have a clear path to managed services.