az-400 Practice Question 1980
Exam: az-400
Domain: Design and implement build and release pipelines
Topic: Design and implement continuous delivery
Difficulty: medium
Your organization wants to minimize downtime during a deployment by using a blue-green deployment strategy. Which of the following best describes this approach?
Answer Options
A
Canary release
B
Two identical environments running different versions of the application
C
Rolling update
D
Blue-green deployment with gradual rollout
Correct Answer
B: Two identical environments running different versions of the application
Explanation
The correct answer is B because in a blue-green deployment, two identical environments (blue and green) exist, each running a different version of the application. The traffic is initially directed to the 'blue' environment, and once the new version is validated, the traffic is switched to the 'green' environment. This minimizes downtime as the transition happens without interrupting service. Option A (Canary release) involves gradually rolling out the new version to a small subset of users to test before full deployment. Option C (Rolling update) involves updating one instance at a time, which can cause temporary downtime. Option D (Blue-green deployment with gradual rollout) combines elements of both blue-green and canary strategies, but the pure blue-green method does not include a gradual rollout component.