Testing New Features on a Separate URL and Reversing Production with a Blue/Green Deployment
You plan to deploy a solution that will include multiple microservices. You need to recommend a deployment strategy for the microservices. The solution must meet the following requirements: • Enable users to test new features by using a specific URL. • Minimize the effort required to promote a test version to production. • Minimize the effort required to revert production code to the previous version. Which strategy should you recommend?
Community Votes
100% of anonymous learners picked answer D. Votes are pick records left by other test-takers — they are not the verified answer.
Community Insight
Blue/green deployment maintains two identical environments side by side, so testing happens on the green URL, promotion is a traffic switch rather than a rebuild, and rollback is switching traffic back to blue, which takes no redeployment at all.
A solution spans multiple microservices and the deployment strategy must let users test new features on a specific URL, minimize the effort to promote a test version to production, and minimize the effort to revert production to the previous version. Three requirements point at a strategy with two parallel environments and a routing switch between them.
Choosing a strategy that optimizes experimentation rather than reversibility. Feature toggles and progressive exposure control who receives a feature at runtime, but they do not give a separate URL to test against and they make promotion a matter of changing flags across microservices rather than a routing switch.
Community Discussion (3 comments)
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Expert Analysis
Why the Answer Is Correct
All three requirements point at blue/green deployment. Testing on a specific URL requires a separate environment that users can be directed to, which green provides. Promoting the tested version to production then becomes a change of routing in the load balancer rather than a rebuild and redeploy, which minimizes the promotion effort. Reverting production becomes switching traffic back to blue, which is the same single routing operation in reverse and therefore requires no redeployment, minimizing the revert effort. The vote was unanimous at 100 for D. uncledana, the highest-liked commenter, identified the rollback capability as the deciding property, and marmila's comment, while brief, agreed.Why the Other Options Are Wrong
The feature toggle strategy (B) controls whether a feature is served to users at runtime, which is valuable for gradual rollout and for hiding incomplete work. It does not satisfy the specific-URL testing requirement, because toggles operate within a single environment rather than providing a parallel environment to test against, and promoting to production means changing toggle states across every microservice rather than performing one routing switch. Progressive exposure (C) is likewise a ramp mechanism that serves the new version to an increasing percentage of users within the same environment, so it neither offers a dedicated test URL nor an instant revert. The A/B strategy (A) compares variants for a limited population to measure which performs better, which is an experimentation design rather than a promotion and rollback mechanism, and its analysis overhead is the opposite of minimal effort here.Community Comment Notes
The community was unanimous at 100 for D, and the substance comments are short but point at the decisive property. uncledana stated that blue/green supports rollback if needed, which is the requirement that separates it from the other three options, since none of them makes reverting production a single traffic switch. marmila's comment is brief agreement with the same conclusion. The comments do not engage with the nuance that blue/green carries a database migration risk when the schema changes alongside the code, which is worth knowing in practice but is outside what this question asks.Related Analysis
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