Which deployment approach uses a duplicate production environment to validate changes before directing traffic to it?

• A. Blue-green deployment
• B. Canary deployment
• C. Rolling deployment
• D. Hotfix

Answer: (A)

The idea being tested is using a duplicate production environment to validate changes before making them live. In a blue-green deployment, two identical production environments exist: one handles live traffic, while the other acts as a ready-to-switch copy where you deploy and thoroughly validate the new version. Once the new environment is confirmed to be stable, traffic is redirected from the old to the new environment, minimizing downtime and reducing risk if a rollback is needed. This approach contrasts with methods that gradually expose users to changes or apply patches directly to the live system, such as canary deployments that route a small portion of traffic to the new version, rolling deployments that update instances step by step, or hotfixes that patch production without switching to a parallel environment.