Blue/Green Deployments: A deployment methodology that runs two production environments while keeping your live and testing environments separate.

- When would I use it?

By having a live and test group of Blue/Green servers, your team can easily rollback workload and traffic from your newest servers to a previous version that you know is working. This assumes you already have multiple cloud deployments set up that are using the practice of immutable infrastructure.

Internally, you can treat one production environment as a testing environment while the other is live and being used. When satisfied with the test environment’s viability, the team can simply re-route all workload from the live server group to the test server group, swapping their roles. If any critical issues arise, the team can rollback to the previous live server that they knew was working and minimizing any downtime for users.

- Can this be used with Canary Deployments?

Yes! Canary deployment is meant to identify problems with a small sample group - Blue/Green deployment is intended to allow an immediate rollback to a previously working version as soon as any problems arise.

This post is part of a series of posts that describe features in Spinnaker. You can find all of the related posts here.