Cloud migration checklist: 14 steps to move without downtime
Every migration our team runs follows the same discipline. Whether it's a two-server monolith or a fifty-workload estate, the steps are the same — only the scale changes. Here is the checklist we use, condensed for teams planning their own move.
Phase one: assess before you touch anything
1. Inventory everything
List every server, database, cron job, certificate, and manual step that "just happens." Anything undocumented will break your migration. Our discovery scripts catch what spreadsheets miss.
2. Map dependencies
Draw how workloads talk to each other, to databases, and to third-party APIs. This dependency map decides migration order and cuts the risk of moving the "wrong thing first."
3. Baseline your cost and performance
Record current spend, CPU, memory, and latency. You cannot prove you improved anything — including cloud cost — without a baseline to compare against.
Phase two: design the target
4. Choose the right provider and services
AWS, Azure, and GCP all work. Pick based on managed services that fit your stack, data residency needs, and your team's existing skills — not brand preference.
5. Design the landing zone
Networking, identity, logging, and backup are the foundations. Nail them first; they are painful to retrofit later. Everything as code, from day one.
6. Decide the strategy per workload
Lift-and-shift, re-platform to managed services, or full modernization. Be honest: re-platforming usually delivers 80% of the value at 20% of the cost.
Phase three: stage and test
7. Rebuild in a shadow environment
Stand up the target side-by-side with production. Never test a migration live for the first time.
8. Replicate data continuously
Use database replication and file sync so the shadow environment stays current, making cutover a switch rather than a bulk copy.
9. Rehearse the cutover
Run the full cutover in staging, including the rollback. Practice turns an outage window into a quiet afternoon.
Phase four: cut over and verify
10. Use blue-green switchover
Point traffic at the new environment, watch health checks, and keep the old environment ready to flip back if anything looks wrong.
11. Validate with real checks
Automated smoke tests for critical flows, then spot-check monitoring, backups, and disaster recovery on the new estate before calling it done.
12. Keep the rollback plan warm
Do not decommission the old environment until the new one has survived a full business week without issues.
Phase five: optimize after the dust settles
13. Right-size and review cost
Move from "as provisioned" to "as used." Right-size instances, add autoscaling, and schedule non-production resources off-hours.
14. Automate ongoing governance
Budget alerts, cost tagging, and reserved capacity planning keep month two as predictable as day one. Pair this with our managed DevOps care if you want it looked after.
“The plan is nothing; planning is everything. Every migration we've seen fail, failed in the assessment phase, not the cutover.” — Neha Malhotra, CTO
Doing it with a team
If you'd rather not run this checklist alone, our cloud migration service does exactly this end-to-end — fixed scope, zero-downtime cutover, and a verified rollback plan. Request a free assessment and we'll send you a cost-and-risk model before you commit to anything.
Related reading
CI/CD pipeline best practices
Once you're on the cloud, deploy to it safely.
Monolith vs microservices
Should you modernize during the move? Start here.