BlauGrünDeployment

BlauGrünDeployment is a software deployment technique that relies on two production environments kept as identical as possible. In normal operation, one environment serves live traffic while the other holds the version to be released. When the new version is ready, traffic is switched from the current live environment (often called blue) to the inactive environment (green), making the update active with minimal downtime. The previous environment can be retained as a rollback option or repurposed for the next release.

Implementation typically involves maintaining parallel production-like environments, with careful attention to data consistency and configuration drift. The release is deployed to the inactive environment, followed by verification tests, automated checks, and performance monitoring. If validation passes, a traffic switch is performed via the load balancer, DNS, or service mesh, and the new version becomes the live environment. The roles may be swapped again as part of a future release pipeline.

Advantages of BlauGrünDeployment include near-zero downtime, immediate rollback capability, and reduced risk of exposing an incomplete release. It also supports testing in a production-like setting before traffic fully shifts. Limitations include increased infrastructure costs, the need to synchronize data stores and configurations to avoid drift, and potential complexity when handling stateful services or database migrations.

It is widely used in cloud environments and modern software delivery practices, especially where continuous deployment and rapid rollback are priorities. The approach is closely related to red–blue deployment and can be combined with canary releases and feature flags to control exposure and validation.