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Walkthrough: Google Associate Cloud Engineer Exam Question on Deployment Strategies
Learn how to tackle a GCP-ACE exam question about deployment strategies. Understand the best choice and why others fall short.
Deploying applications in Google Cloud requires careful planning for version management. Candidates often trip on deployment strategies, especially when considering rollback options. Choosing the right method can impact application reliability and user experience.
The question
You are deploying a new application to Google Cloud and need to ensure that it can easily roll back to a previous version if necessary. Which deployment strategy should you use?
A. Blue/Green Deployment
B. Rolling Update
C. Canary Deployment
D. Recreate Deployment
Think before you scroll
Consider the rollback implications of each deployment strategy. Some methods allow gradual rollouts but may complicate reverting to a previous version. Weigh the ease of switching back to the last stable version against the rollout process of each option.
The answer
The correct option is A. Blue/Green Deployment. This strategy uses two identical environments: one that is live and one that is idle. If a rollback is necessary, switching back to the previous version is quick and straightforward. This clarity makes it the best choice for managing deployments where stability is crucial.
Why the other options lose
- B. Rolling Update: This method updates instances gradually, reducing downtime. However, if issues arise, rolling back can be complex as it involves stopping the update process and managing multiple active versions. This makes it less ideal for straightforward rollbacks.
- C. Canary Deployment: This approach tests new versions with a small subset of users. While it allows for early detection of issues, rolling back to a previous version requires additional steps to switch back the entire user base, complicating the rollback process.
- D. Recreate Deployment: This strategy stops the existing version and starts the new one. While it is simple, it does not provide a straightforward rollback option. Once the new version is live, reverting to the old version requires redeployment, making it inefficient for quick rollbacks.
The concept behind it
Understanding deployment strategies is crucial for cloud engineers. The Blue/Green strategy stands out for its simplicity in rollback. It provides a clear separation between the live and idle environments, allowing for easy switching. In contrast, other strategies prioritize gradual updates or testing, which can complicate rollback efforts.
Exam trap to remember
Remember: For quick rollbacks, choose Blue/Green Deployment. This choice minimizes disruption and maximizes control over application versions.