Application Deployment Strategies (Blue/Green, Canary) Questions and Answers for Viva

Answer-1: Blue/Green deployment is a strategy where two identical production environments (Blue and Green) are used to reduce downtime and risk by switching traffic between them.

Answer-2: Canary deployment gradually shifts traffic to a new version with a small subset of users before full rollout, while Blue/Green switches all traffic at once.

Answer-3: Minimal downtime, easy rollback, and reduced risk during deployment.

Answer-4: Gradual rollout reduces impact of bugs and allows monitoring with real users before full release.

Answer-5: For critical applications requiring quick rollback and minimal downtime, Blue/Green is preferred.

Answer-6: When you want to test new features on a subset of users or environments to monitor performance and errors.

Answer-7: Resource duplication costs and potential data synchronization issues between environments.

Answer-8: Incomplete testing on limited users and complexity in traffic routing.

Answer-9: Simply redirect traffic back to the previous (Blue or Green) environment.

Answer-10: Stop or roll back the new version and gradually shift traffic back to the stable version.

Answer-11: It directs user traffic to either Blue or Green environment based on deployment status.

Answer-12: Monitoring allows early detection of issues on the small user group before full rollout.

Answer-13: Database changes require careful planning, often involving backward-compatible migrations to avoid issues.

Answer-14: Gradually increasing the percentage of user requests directed to the new version.

Answer-15: By exposing new features to a small group of users and collecting feedback and metrics.

Answer-16: Yes, deployment automation tools can handle environment provisioning and traffic switching.

Answer-17: Kubernetes, AWS CodeDeploy, Jenkins, Spinnaker, and Istio.

Answer-18: Using deployment strategies like rolling updates and traffic routing with service mesh.

Answer-19: Releasing new features to production but hiding them from users, often combined with Canary deployments.

Answer-20: Ensure both environments share session state or use stateless sessions.

Answer-21: Feature flags allow toggling new features on/off without redeploying.

Answer-22: Error rates, latency, resource usage, and user feedback.

Answer-23: Rolling deployment updates instances incrementally and is often used as a form of Canary deployment.

Answer-24: By using backward-compatible schema changes and data migration strategies.

Answer-25: Ensuring both old and new versions are compatible with the database during gradual rollout.

Answer-26: Traffic routers direct a small percentage of users to the new version and the rest to the stable one.

Answer-27: Yes, traffic switching allows almost zero downtime deployments.

Answer-28: Based on risk tolerance and monitoring feedback, starting small and increasing gradually.

Answer-29: A predefined procedure to revert to the previous stable version in case of failure.

Answer-30: By enabling or disabling features dynamically, reducing the need for full redeployments.

Answer-31: Yes, you can use Blue/Green for environment setup and Canary for gradual traffic shifting.

Answer-32: An automated process that builds, tests, and deploys code changes.

Answer-33: By providing frequent, tested builds for safe incremental releases.

Answer-34: Segmenting users helps test features on targeted groups before full rollout.

Answer-35: Maintain separate configurations per environment and synchronize as needed.

Answer-36: Automation ensures consistency, repeatability, and reduces human error during deployments.

Answer-37: By monitoring system health, user feedback, and key performance metrics.

Answer-38: It requires duplicating environments which can increase infrastructure costs.

Answer-39: By exposing new changes to a small user base first to catch issues early.

Answer-40: Canary release deploys new code to a subset of users; feature toggles enable/disable features in existing code.

Answer-41: By regularly rehearsing rollbacks in staging or production-like environments.

Answer-42: Data synchronization and latency can complicate environment switching.

Answer-43: They provide advanced traffic routing and telemetry capabilities.

Answer-44: A bug causing errors only under specific user conditions during gradual rollout.

Answer-45: By creating detailed runbooks and checklists accessible to deployment teams.

Answer-46: Yes, by switching traffic between different versions of serverless functions.

Answer-47: It allows independent rollout and testing of services without full system downtime.

Answer-48: Through dashboards, alerts, and regular status updates to stakeholders.

Answer-49: By reducing risk of widespread issues and allowing smoother transitions.

Answer-50: Application criticality, complexity, downtime tolerance, and infrastructure costs.