Most cloud migrations do not fail because of technology. They fail because of a missing initial inventory, unrealistic timelines and no documented rollback plan. The typical result is a project that runs twice as long, costs more than budgeted and leaves a team exhausted from managing two parallel infrastructures.
The first step nobody does well: the honest inventory
The first step is an honest inventory: what systems exist, who uses them, how often and what would happen if they were down for four hours. Without that, any migration plan is fiction. Most inventories we see have between 20 and 40% of systems that nobody knew were in production until someone asked.
- Complete list of systems with an assigned business owner (not just a technical contact)
- Criticality by time window: what happens if it is down for 1h, 4h, 24h
- System dependencies: which application needs another one to be available first
- Current state: version, OS, last patch date, whether it has active support
- Real usage frequency: some systems appear critical on paper but are used monthly
The 6 Rs and the first year that always costs more
The '6 R' framework (rehost, replatform, refactor, repurchase, retire, retain) remains the practical reference. For most SMEs, 70% of systems go to rehost and 20% to retire. The remaining 10% is where the real work and most of the budget are.
- Rehost (lift and shift): move the system as-is to cloud. Fast, cheap, no optimisation.
- Replatform: migrate with minor adjustments to use cloud services (managed database, etc.).
- Refactor: redesign the application to be cloud-native. Expensive, slow, but higher long-term benefit.
- Repurchase: replace with a SaaS equivalent (moving from own Exchange server to Microsoft 365).
- Retire: shut down systems that are no longer used. The easiest 20% and frequently overlooked.
- Retain: keep on-premise for technical, regulatory or cost reasons.
A well-planned cloud migration is not a technical project — it is a business project with a technical component. Decisions about what to migrate, when and at what pace must be made with the context of what the business can afford in terms of operational risk and interruption window.
If you are planning a cloud migration or want to understand what it involves before committing, we can help you evaluate options without commercial pressure.
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