Exam Professional Cloud DevOps Engineer topic 1 question 158 discussion

https://cloud.google.com/architecture/application-deployment-and-testing-strategies#shadow_test_pattern With shadow testing, you deploy and run a new version alongside the current version, but in such a way that the new version is hidden from the users, as the following diagram shows. An incoming request is mirrored and replayed in a test environment. This process can happen either in real time or asynchronously after a copy of the previously captured production traffic is replayed against the newly deployed service.

Choose option D. Shadow testing allows the deployment and execution of a new version alongside the current one, but in a manner that is hidden from users. This approach ensures zero production impact, as the incoming requests are mirrored and replayed in a test environment. By duplicating traffic, it enables comprehensive testing of new features and improvements against the full production load without affecting end-users. Additionally, the continuous deployment aspect ensures that the deployment process remains ongoing, allowing for iterative testing and refinement based on real-world performance metrics and user interactions before a full rollout occurs.

Vote D

Shadow testing is a technique where you deploy a new version of your application alongside the existing production version, but you don't route live traffic to it. Instead, you route a copy of the live traffic to the new version (the "shadow" version) while the production version continues to serve real user traffic. This allows you to gather performance metrics and test the new version under real-world conditions without affecting the end users' experience.

https://cloud.google.com/architecture/application-deployment-and-testing-strategies#shadow_test_pattern

Option A is literally for spilting traffic between versions , Canary is gradually allowing traffic to production, D is right answer