Data & cloud migrations Practical guide

Map the dependencies before you move the workload

Plan a migration around the data, connections, and validation that keep the business running.

A migration plan needs more than a destination and a transfer date. It needs a clear picture of what the workload reads, writes, calls, and depends on, including the systems outside the team’s direct control.

Start with one representative workload. Use it to make the approach concrete before planning the wider move.

Draw the connections

List applications, databases, scheduled jobs, queues, identity services, and external integrations. Record the direction of each connection and who owns both ends.

Include the less visible paths: reports, exports, background workers, and people who consume files manually. A system diagram is useful when it describes how the business actually works.

Give the data a plan of its own

For each dataset, record its source, destination, size, change rate, and validation method. Decide how updates made during the move will reach the destination.

Assign responsibility for checking the result. A transfer completing does not establish that the application is reading the right data or that downstream reports still make sense.

Write the cutover as a sequence

Document the steps, their owners, and the checks required to continue. Include changes to traffic, credentials, scheduled work, and dependent systems.

Agree on a decision point for stopping or reversing the move. A rollback plan should describe the state of the data as well as the application. Some changes cannot be safely reversed just by switching traffic back.

Rehearse the uncertain parts

Test the steps most likely to create surprises: restoring a dataset, changing a connection, validating permissions, or catching up writes. Record how long they take and which assumptions fail.

Use that evidence to update the plan. Avoid treating a rehearsal as a ceremony that confirms a date already chosen.

Validate the business flow

Before declaring the move complete, test the transactions and outputs that matter to users. Compare expected results, inspect monitoring, and confirm that the people operating the service can find the information they need.