What Are Blue-Green Deployments in Kubernetes?

Kubernetes is a container orchestrator that automates the deployment and scaling of containerized applications. Blue-green deployments are a popular strategy in Kubernetes, running two versions of an app side-by-side with traffic directed to the old release until promoting the new one. This improves operational resilience and allows developers to test changes safely without exposing them directly to users. Three main ways to implement blue-green deployments in Kubernetes include manually setting up using a Kubernetes Service, using Argo rollouts, or using Flux CD and Flagger. Benefits of blue-green deployments include safe production tests, immediate rollbacks on failure, downtime-free release promotion, ease of deployment, and reliability. However, disadvantages include resource intensity, potential downtime during schema upgrades, and high costs. Alternative strategies for Kubernetes workloads include canary deployments, A/B deployments, best-effort rollouts, and rolling updates. Spacelift is a tool that helps manage Kubernetes projects by providing a GitOps flow, custom policies, and various features to enhance security and reliability.