What is a commonly used method to ensure code deployment does not disrupt existing services?

Blue/green deployment is a widely adopted strategy for minimizing disruptions during code deployment. This method involves maintaining two separate environments – one (the blue environment) that is currently active and serving user traffic, and another (the green environment) where the new version of the application is deployed and tested.

Once the new version is verified in the green environment and deemed stable, traffic is switched from the blue environment to the green environment. The switch can be executed instantly, allowing users to access the new version with minimal downtime. This approach not only reduces deployment risks but also provides a quick rollback option: if issues arise with the new version, traffic can easily be redirected back to the blue environment.

While the other strategies mentioned, such as canary deployments and rolling deployments, are also effective in their own right and serve to address specific deployment needs, blue/green deployments stand out for their ability to handle traffic switching seamlessly and for their straightforward rollback capability. Just-in-time deployment generally focuses more on optimizing updates rather than direct service continuity, which makes blue/green deployment the preferred choice for minimizing service disruption during deployments.