Google Professional-Cloud-DevOps-Engineer - Google Cloud Certified - Professional Cloud DevOps Engineer Exam

https://sre.google/sre-book/service-level-objectives/

The best option for preparing to handle the predicted growth is to verify the maximum node pool size, enable a Horizontal Pod Autoscaler, and then perform a load test to verify your expected resource needs. The maximum node pool size is a parameter that specifies the maximum number of nodes that can be added to a node pool by the cluster autoscaler. You should verify that the maximum node pool size is sufficient to accommodate your expected growth rate and avoid hitting any quota limits. The Horizontal Pod Autoscaler is a feature that automatically adjusts the number of Pods in a deployment or replica set based on observed CPU utilization or custom metrics. You should enable a Horizontal Pod Autoscaler for your application to ensure that it runs enough Pods to handle the load. A load test is a test that simulates high user traffic and measures the performance and reliability of your application. You should perform a load test to verify your expected resource needs and identify any bottlenecks or issues.

https://sre.google/sre-book/service-level-objectives/

You want the application's SLO to more closely reflect it's observed reliability. The key here is error budget never goes over 5%. This means they can have additional downtime and still stay within their budget.

The best option for centralizing the logs generated by Google Cloud services from all projects only inside your production folder is to create an aggregated log sink associated with the production folder that uses a Cloud Logging bucket as the destination. An aggregated log sink is a log sink that collects logs from multiple sources, such as projects, folders, or organizations. A Cloud Logging bucket is a storage location for logs that can be used as a destination for log sinks. By creating an aggregated log sink with a Cloud Logging bucket, you can collect and store all the logs from the production folder in one place and allow for alerting and near-real time analysis using Cloud Monitoring and Cloud Operations.

https://cloud.google.com/kubernetes-engine/docs/tutorials/autoscaling-metrics

The Google Cloud HTTP Load Balancer (GCLB) provides metrics on the number of requests and the response latency for each backend service. These metrics can be used as custom metrics for the horizontal pod autoscaler (HPA) to scale the deployment based on the load. This is the correct solution to use an appropriate SLI for scaling.

https://cloud.google.com/monitoring/api/metrics_gcp#gcp-appengine

The correct answer is A. Notify the team that their error budget is used up. Negotiate with the team for a launch freeze or tolerate a slightly worse user experience.

According to the Site Reliability Engineering (SRE) practices, an error budget is the amount of unreliability that a service can tolerate without harming user satisfaction1.An error budget is derived from the service-level objectives (SLOs), which are the measurable goals for the service quality2. When a service exceeds its error budget, it means that it has violated its SLOs and may have negatively impacted the users.In this case, the SRE team should notify the product team that their error budget is used up and negotiate with them for a launch freeze or a lower SLO3. A launch freeze means that no new features are deployed until the service reliability is restored. A lower SLO means that the product team accepts a slightly worse user experience in exchange for launching new features. Both options require a trade-off between reliability and innovation, and should be agreed upon by both teams.

The other options are incorrect because they do not follow the SRE practices.Option B is incorrect because it violates the principle of error budget autonomy, which means that each service should have its own error budget and SLOs, and should not borrow or reallocate them from other services4. Option C is incorrect because it does not address the root cause of the error budget overspend, and may create unrealistic expectations for the service reliability. Option D is incorrect because it does not prevent the possibility of introducing new errors or bugs with the feature launch, which may further degrade the service quality and user satisfaction.

Comprehensive and Detailed Explanation:

To follow GitOps best practices and Google Cloud’s recommended repository structure for Terraform (IaC), Config Sync, and application code, we should use a shared repository for Terraform and Config Sync while keeping application repositories separate.

Cloud Infrastructure (Terraform) repository is shared → This allows infrastructure teams to manage all environments in a single repository with different directories per environment (dev, QA, production). This is the standard approach to structuring Terraform repositories.

GKE Enterprise Infrastructure (Config Sync) repository is shared → Using Kustomize overlays per environment (instead of separate repositories) aligns with Config Sync’s best practices and makes managing configurations easier.

Application repositories are separated, using different branches for features → This allows application teams to follow the Git branching model (feature branches, main branch, release branches, etc.) without affecting infrastructure.

📌Official Reference:

Config Sync Best Practices

Terraform Structure Best Practices

GitOps Best Practices