Blue-green deployments

Blue-green is a development and deployment concept requiring two copies of the product, one called blue and other green, with one copy being the current release of the product. The other copy is in active development to become the next release as soon as it is deemed fit for production. Another benefit of using this development/deployment model is the ability to roll back to the previous release should the need arise. Blue-green deployments are vital to the concept of CI because, without the future release being developed in conjunction with the current release, hotfixes and fire/damage control become the norm, with innovation and overall focus suffering as a result.

Blue-green deployments specifically allow zero-downtime deployment to take place and for rollbacks to occur seamlessly (since the previous instance was never destroyed). Some very notable organizations have successfully implemented blue-green deployments. These companies include:

• Netflix
• Etsy
• Facebook
• Twitter
• Amazon

As a result of blue-green deployments, there have been some very notable successes within the DevOps world that have minimized the risk of deployment and increased the stability of the software systems.