A successful move to AWS is mostly preparation. This checklist covers the ten things that decide whether a migration finishes calmly or turns into a long, expensive scramble.
1. Write down why you are migrating
Cost, resilience, speed of delivery, end of a data-center lease, or a security requirement each lead to different designs. Choose the one or two goals that matter most, and use them to settle later arguments. A migration whose only goal is "move to the cloud" has no way to tell if it worked.
2. Inventory applications, data and dependencies
List every application, database, scheduled job, integration and the people who own them. The surprises that derail migrations are almost always hidden dependencies: a reporting script on a forgotten server, or a firewall rule that only one person understands.
- Applications and owners
- Databases and sizes
- Integrations and file transfers
- Licenses that may not move
- Compliance and data-residency requirements
3. Choose a path for each workload: the 6 Rs
AWS describes six common strategies. Most portfolios use several of them.
- Rehost: move as is, quickest, little cloud benefit
- Replatform: small changes such as a managed database
- Refactor: redesign for cloud-native services
- Repurchase: replace with a SaaS product
- Retire: switch it off
- Retain: leave it where it is for now
4. Build a landing zone before moving anything
Set up accounts, networking, identity, logging and baseline security first. A proper landing zone keeps production separate from testing, limits the damage from mistakes and gives auditors something to look at. Define all of it in Terraform so it can be reviewed and recreated.
5. Decide how containers and compute will run
Many teams get the best balance by packaging applications as containers and running them on Amazon ECS. It reduces the amount of server management, scales cleanly and gives repeatable deployments. Applications that are not ready for containers can start on virtual machines and move later.
6. Plan the data migration carefully
Data is the slowest, riskiest part. Decide how much downtime is acceptable, then pick between a one-time copy and continuous replication followed by a short cutover. Rehearse the cutover on a copy, validate row counts and checksums, and keep the ability to roll back.
7. Secure it from the start
Use least-privilege roles instead of shared keys, encrypt data at rest and in transit, restrict network paths, turn on logging and alerting, and test backups by restoring them. Security added after go-live is slower and more expensive.
8. Automate deployments and infrastructure
Move to a pipeline where infrastructure and application changes are reviewed in version control and applied automatically. This is how you prevent configuration drift, the slow divergence between what is documented and what is actually running.
9. Test, then migrate in waves
Start with a low-risk application to prove the process, then move in waves of related systems. Each wave needs functional tests, performance checks and a go/no-go decision. Automated tests make this much faster and safer.
10. Control cost and review after go-live
Tag resources, set budgets and alerts, right-size instances and delete unused resources. Review the bill weekly in the first months. The first AWS invoice rarely matches the estimate, and the gap is usually fixable with tuning.
Where to get help
If you want an experienced second pair of eyes on a migration plan, or help carrying it out, our AWS cloud consulting service covers each of these steps.