A data migration rollback plan names the exact checkpoint that stops execution, preserves writes made after cutover, provides tested reversal or fail-forward code, and assigns the decision to a person before the window begins.
Define the rollback decision before execution
The migration checklist should state measurable stop conditions such as a reconciliation threshold breach, rejection rate, application error rate, latency ceiling, or failed critical-path read. Each condition names the person who can pause the run and the person who chooses between repair, rollback, and fail-forward. An operator should not invent that authority while production is already partially transformed.
The plan also identifies the last reversible checkpoint. Before new writes reach only the target representation, restoring a backup may be sufficient. After new production data enters the target, returning to a stale source can lose accepted transactions. AWS cutover guidance distinguishes rollback without new data from rollback after changed data and describes dual writes, reverse replication, or tested backup restoration as separate strategies.
Test the script and the restored application path
A rollback script must run against the same schema version and representative state used in rehearsal. The test records duration, affected rows, irreversible fields, restored counts, and every error. It then starts the old application build and exercises sign-in, reads, writes, background jobs, and integrations that depend on the restored data.
A successful database restore can still leave queues, search indexes, object storage, caches, or external systems ahead of the source. The rollback inventory names those dependencies and the action for each one. Some can be rebuilt from the restored database, while others need compensating records or a decision to fail forward instead.
Close with a new reconciliation
Rollback changes data and therefore needs its own control totals. The operator compares the restored or fail-forward state to the last accepted checkpoint, accounts for post-cutover transactions, and records any deferred repair. AWS recommends defined checkpoints, a data-handling strategy, and a named decision contact for migration rollback. The final incident record should show that those conditions were followed rather than treating the return of traffic as proof that the state is correct.
Where the service stops
Reality Contact, LLC prepares and reviews migration code and evidence, but does not authorize production access, operate an unapproved backup, certify regulatory compliance, accept data ownership, or make the final cutover decision. The buyer verifies backups and access controls, approves mappings and thresholds, names the production operators, authorizes the migration window, and runs the approved transformation against production. The service is technical implementation and document preparation, and it does not replace the buyer's database administrator, security review, compliance process, backup ownership, or production authorization. The buyer controls credentials, backups, production execution, acceptance thresholds, and every decision to continue, pause, roll back, or fail forward.
Sources: AWS migration cutover and rollback guidance; PostgreSQL upgrade compatibility checks.