DevOps
What is Rollback?
Reverting a system to a previous known-good version after a bad deployment, restoring service while the failure is investigated.
Definition
A rollback returns production to the last known-good state after a release goes wrong. Mechanisms vary: redeploying the previous container image, flipping traffic back in a blue-green setup, kubectl rollout undo for a Kubernetes Deployment, or reverting the commit in a GitOps repo and letting the pipeline reconcile. Fast rollback depends on immutable, versioned artifacts and on database migrations that are backward compatible — a schema change the old code can't read makes rollback impossible. Mature teams measure mean time to recovery and rehearse rollbacks rather than treating them as emergencies.