PCD Practice Test 13 — 15 Questions

Question 1

Drag and drop the steps to set up a Cloud Build trigger for continuous deployment in the correct order.

Accepted Answer

1. Connect your repository (e.g., GitHub, Cloud Source Repositories). 2. Create a new trigger in Cloud Build. 3. Configure the trigger event (e.g., push to a specific branch). 4. Specify the build configuration file (e.g., cloudbuild.yaml).. A Cloud Build trigger is set up by connecting a repository and configuring the conditions for automatic builds.

Answer

1. Create a new trigger in Cloud Build. 2. Connect your repository. 3. Configure the trigger event. 4. Specify the build configuration file.

Answer

1. Configure the trigger event. 2. Connect your repository. 3. Create a new trigger in Cloud Build. 4. Specify the build configuration file.

Answer

1. Specify the build configuration file. 2. Connect your repository. 3. Create a new trigger in Cloud Build. 4. Configure the trigger event.

Question 2

You are configuring a Cloud Spanner database for a financial application. You need to ensure that queries on the 'Orders' table by 'customer_id' are efficient without performing a full table scan. You also want to avoid index joins when possible. Which TWO actions should you take?

Accepted Answer

Use the STORING clause to include frequently queried columns in the index. The STORING clause in a Cloud Spanner secondary index allows you to include additional columns (e.g., frequently queried columns) directly in the index entries. This enables index-only scans, avoiding the need for an index join (back join) to fetch data from the base table, thus improving query efficiency. Option E is correct because creating a secondary index on 'customer_id' directly supports efficient point lookups and range scans on that column, preventing full table scans.

Answer

Create a global secondary index on 'order_id'

Answer

Partition the table by customer_id

Answer

Use the INTERLEAVE IN clause to create a local index

Question 3

A startup is deploying a stateless web app on Compute Engine. They expect traffic spikes. What is the most cost-effective way to handle scaling?

Accepted Answer

Use managed instance groups with autoscaling based on CPU utilization.. Managed instance groups (MIGs) with autoscaling based on CPU utilization are the most cost-effective solution for a stateless web app with traffic spikes because they automatically add or remove VM instances in response to real-time CPU load, ensuring you only pay for the compute resources you actually use. This approach directly matches the stateless nature of the app, allowing instances to be created and destroyed without data loss, and avoids over-provisioning or under-utilizing resources.

Answer

Use App Engine Standard.

Answer

Use a single large VM with more cores.

Answer

Use Cloud Functions.

Question 4

A startup wants to deploy a web application on App Engine standard environment. They need to handle sudden traffic spikes automatically. How should they configure scaling?

Accepted Answer

Use automatic scaling.. Automatic scaling is the correct choice because App Engine standard environment natively supports automatic scaling, which dynamically adds or removes instances based on request rate, latency, and other metrics. This allows the application to handle sudden traffic spikes without manual intervention, as the platform automatically provisions resources to meet demand.

Answer

Use basic scaling with idle timeout.

Answer

Use manual scaling with a fixed number of instances.

Answer

Use a combination of manual and automatic scaling.

Question 5

You need a database that provides 99.999% availability SLA, global distribution, and supports ACID transactions across regions. Which Google Cloud database meets these requirements?

Accepted Answer

Cloud Spanner. Cloud Spanner is the only Google Cloud database that provides 99.999% availability SLA, global distribution via automatic synchronous replication across regions, and full ACID transactions across regions using TrueTime and Paxos-based consensus. It combines horizontal scalability with strong consistency, making it ideal for globally distributed applications requiring transactional integrity.

Answer

Bigtable

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Cloud SQL

Answer

Firestore

Question 6

A company has a monorepo with multiple services. They want to only build and test the services that have changed in a given commit. Which Cloud Build feature should they use?

Accepted Answer

Build triggers with filepath filters. Cloud Build triggers with filepath filters allow you to specify glob patterns that match changed files in a commit. When a commit includes changes only to files matching the filter, the trigger runs; otherwise, it is skipped. This enables selective building and testing of only the services that have changed in a monorepo, avoiding unnecessary builds for unaffected services.

Answer

Use a custom builder image

Answer

Build triggers with branch filters

Answer

Use Cloud Build substitutions

Question 7

A company receives a Cloud Monitoring alert that a Compute Engine instance's CPU utilization has exceeded 90% for the past 15 minutes. The incident turns out to be a false alarm caused by a scheduled job that runs daily. How can they prevent future false alarms for this recurring pattern?

Accepted Answer

Create a custom metric that excludes the scheduled job's CPU usage and use it in the alert.. Creating a custom metric that excludes the scheduled job's CPU usage allows the alert to ignore the predictable, recurring spike. This approach uses Cloud Monitoring's custom metrics capability to filter out known noise, ensuring the alert only triggers on unexpected CPU utilization patterns.

Answer

Switch to 'Metric Absence' type condition.

Answer

Increase the CPU utilization threshold to 95%.

Answer

Change the condition's 'for' duration to 30 minutes.

Question 8

Refer to the exhibit. A developer configured a Pub/Sub push subscription to a Cloud Run service. Messages are not being delivered to the Cloud Run service. The developer verified that the service is running and the IAM permissions are correct. What is the most likely issue?

Accepted Answer

The OIDC token audience does not match the Cloud Run service's URL. The most likely issue is that the OIDC token audience does not match the Cloud Run service's URL (Option B). For push subscriptions with OIDC authentication, the audience must exactly match the service URL. Option A is incorrect because the service account needs the token creator role, not the pubsub.publisher role. Option C is incorrect because the endpoint shown is HTTPS. Option D is incorrect because ackDeadlineSeconds affects processing time, not delivery; messages not being delivered indicates an authentication or endpoint issue.

Answer

The service account does not have the pubsub.publisher role

Answer

The push endpoint URL is not a valid HTTPS endpoint

Answer

The ackDeadlineSeconds is too short for the Cloud Run service to process messages

Question 9

An organization uses Cloud Build to deploy multiple microservices to GKE. They want to ensure that the deployment process can be audited and that each deployment can be rolled back to a previous version. What is the recommended approach?

Accepted Answer

Use Cloud Deploy to manage deployments with rollback capabilities and audit logs.. Cloud Deploy is the recommended service for managing progressive deliveries and rollbacks on GKE, as it provides built-in rollback capabilities, audit logging, and delivery pipeline management. Unlike raw Kubernetes Deployment history, Cloud Deploy integrates with Cloud Build and offers a controlled, auditable deployment process with the ability to roll back to any previous release revision.

Answer

Use Kubernetes Deployment history to rollback by specifying a revision.

Answer

Store each manifest version in Artifact Registry and manually apply kubectl.

Answer

Use Cloud Build to redeploy a previous image tag when rollback is needed.

Question 10

A developer ran the following command: `gcloud compute instances list --filter='labels.env=prod'`. The command returned no instances even though there are instances with label env=prod. What is the most likely reason?

Accepted Answer

The filter syntax is incorrect; should use `labels.env:prod`.. The correct filter syntax for labels uses a colon (:) instead of an equals sign. The proper filter is `labels.env:prod`. Option A is wrong because if the project were different, a different error would appear. Option B is wrong because permission errors produce a different message. Option D is wrong because stopped instances are still listed.

Answer

Instances are in a different project.

Answer

The user lacks compute.instances.list permission.

Answer

The instances are stopped.

Question 11

A company has a Cloud Run service that ingests messages from a Cloud Pub/Sub subscription. The service uses automatic scaling based on CPU. Recently, the team noticed that when message volume spikes, the service scales up slowly, causing a backlog. What is the most effective solution to reduce the time to scale out?

Accepted Answer

Change the subscription type from pull to push and set the Cloud Run service as the push endpoint.. Using a push subscription from Pub/Sub directly triggers Cloud Run invocations, which reduces latency compared to pull subscriptions that require polling. This improves scaling responsiveness during traffic spikes. Option A is wrong because increasing max instances does not accelerate scaling speed; it only sets an upper limit. Option B is wrong because adding Cloud Tasks and Cloud Scheduler introduces extra latency without solving the scaling delay. Option C is wrong because setting a minimum number of instances can reduce cold starts but does not speed up scaling from zero to the minimum; it only ensures a base level of instances are always running.

Answer

Increase the max instances for the Cloud Run service to 100.

Answer

Use Cloud Tasks to buffer messages and configure a Cloud Scheduler job to pull from the queue.

Answer

Set a minimum number of instances on the Cloud Run service to 5.

Question 12

A company uses Cloud SQL for MySQL. They need to export data to Cloud Storage regularly. What is the recommended method?

Accepted Answer

Use Cloud SQL export feature to export to Cloud Storage.. The recommended method to export data from Cloud SQL for MySQL to Cloud Storage is to use the built-in Cloud SQL export feature (Option D). This feature allows you to export data directly to Cloud Storage in formats like SQL or CSV, providing a secure and managed process without external tools. Option A (Dataflow) is not recommended for simple exports as it adds unnecessary complexity and cost. Option B (cron job on Cloud SQL instance) is not supported; Cloud SQL does not allow running cron jobs on the instance. Option C (mysqldump from Compute Engine) is manual, requires additional security configurations, and is less efficient than the built-in export.

Answer

Use Dataflow to read from Cloud SQL and write to Cloud Storage.

Answer

Use a cron job on Cloud SQL instance to write to Cloud Storage.

Answer

Use mysqldump command from a Compute Engine instance.

Question 13

A team is developing a REST API on Cloud Run. They need to ensure that only authenticated requests from their corporate domain (example.com) are allowed. Which configuration should they use?

Accepted Answer

Set the Cloud Run service to require authentication and allow only the domain 'example.com' in the IAM policy. Cloud Run's IAM integration allows you to require authentication (via the `--no-allow-unauthenticated` flag) and then use IAM conditions to restrict access to principals from a specific domain (e.g., `request.auth.claims.email` ends with `@example.com`). This ensures only authenticated requests from the corporate domain are permitted, leveraging Google Cloud's identity-aware proxy (IAP) capabilities without additional infrastructure.

Answer

Implement custom authentication using Firestore to validate user tokens

Answer

Use Cloud Endpoints with an API key that is shared only with corporate users

Answer

Use Cloud Armor to deny traffic except from the corporate IP range

Question 14

A team is implementing a CI/CD pipeline for a Cloud Function using Cloud Build. Which three steps should they include in their cloudbuild.yaml? (Choose 3)

Accepted Answer

Static code analysis. Static code analysis (A) is correct because it helps identify code quality issues, security vulnerabilities, and adherence to coding standards early in the pipeline, which is a best practice for Cloud Functions. Running unit tests (C) is essential to validate function logic before deployment. Deploying the function (B) is the final step that pushes the validated code to Cloud Functions, making it a required step in the CI/CD pipeline.

Answer

Build a container image

Answer

Manual approval step

Question 15

A team is migrating a monolithic application to microservices on Google Kubernetes Engine (GKE). They want to ensure that if one microservice fails, it does not cascade to other services. Which design pattern should they implement?

Accepted Answer

Circuit Breaker pattern. The Circuit Breaker pattern is correct because it prevents cascading failures by monitoring for failures in a downstream microservice and, once a threshold is exceeded, immediately failing requests to that service without attempting the call. In GKE, this can be implemented using tools like Istio or Envoy sidecar proxies, which can be configured with circuit breaker settings to stop traffic to unhealthy pods, allowing the system to recover gracefully.

Answer

Event-driven architecture

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Retry with exponential backoff

Answer

Bulkhead pattern