Google PCA Practice Test 4 — 10 Questions

Question 1

A company runs an e-commerce platform on Google Cloud. The application is deployed on Google Kubernetes Engine (GKE) with a regional cluster (us-central1, three zones). The frontend service is exposed via an HTTP Load Balancer with Cloud CDN. Recently, during a flash sale, users experienced high latency and occasional 502 errors. The backend service is a Java application that reads from Cloud Spanner. The team has observed that Spanner CPU utilization averaged 65% during the sale, with a few spikes to 80%. The number of frontend pods was auto-scaled to 50, each running on n1-standard-2 nodes. The node pool is set to autoscale up to 100 nodes. The errors appear to correlate with periods of high CPU on the nodes, but not always. What is the most likely cause and recommended action?

Choose an answer to begin — your selection is scored in the full session.

Accepted Answer

Change the backend service to use a multi-zone NEG that includes endpoints from all three zones, and ensure the load balancer is configured for cross-zone load balancing.. The high latency and 502 errors are likely caused by the HTTP Load Balancer sending requests to unhealthy backend pods due to zone-imbalanced traffic. A regional GKE cluster with a multi-zone NEG and cross-zone load balancing ensures that the load balancer distributes requests evenly across all pods in all three zones, preventing node CPU spikes in a single zone from causing errors. Option B directly addresses this by enabling proper traffic distribution, which is the most probable root cause given that node CPU spikes correlate with errors but not always.

Answer

Scale up the Cloud Spanner instance to handle higher peak CPU, as the 80% spikes indicate insufficient capacity.

Answer

Increase the CPU request for the frontend pods and set a higher target CPU utilization for the Horizontal Pod Autoscaler.

Answer

Increase the health check interval and timeout settings to give pods more time to respond before being marked unhealthy.

Question 2

Drag and drop the steps to deploy a containerized application to Google Kubernetes Engine (GKE) using a Deployment into the correct order.

Accepted Answer

Build the container image, then push the image to a registry, then create a Deployment manifest, then apply the Deployment to the cluster, then create a Service to expose the application.. The image must be in a registry before the Deployment can reference it. The Service provides external access.

Answer

Build the container image, then push the image to a registry, then create a Service, then create a Deployment manifest, then apply the Deployment.

Answer

Build the container image, then create a Deployment manifest, then push the image to a registry, then apply the Deployment, then create a Service.

Answer

Create a Deployment manifest, then apply the Deployment, then build the container image, then push the image to a registry, then create a Service.

Question 3

A Cloud Router BGP session is flapping. The logs show 'Interface flapping due to changes in the underlying network'. What is the most likely cause?

Accepted Answer

MTU mismatch across the network path.. The log message 'Interface flapping due to changes in the underlying network' indicates that the BGP session is unstable because the physical or logical interface is going up and down. An MTU mismatch across the network path can cause packet fragmentation issues, leading to intermittent connectivity and interface flaps as the router detects and recovers from the problem. This is the most likely cause because it directly affects the stability of the underlying network path.

Answer

BGP MD5 authentication failure.

Answer

Incorrect local AS number in Cloud Router configuration.

Answer

BGP timer misconfiguration between peers.

Question 4

A financial services company requires a globally distributed relational database with strong consistency and horizontal scalability to serve a multi-region banking application. Write conflicts are rare. Which database should they choose?

Accepted Answer

Cloud Spanner. Cloud Spanner is the only Google Cloud database that provides global distribution, strong consistency, and horizontal scalability for relational workloads. It uses true-time technology for external consistency. Bigtable is NoSQL; Firestore is eventually consistent; Cloud SQL is regional.

Answer

Firestore in Native mode

Answer

Cloud SQL with cross-region replication

Answer

Cloud Bigtable

Question 5

A startup is designing a real-time leaderboard for a multiplayer game. The leaderboard must update within seconds of a score change and handle millions of concurrent players. Strong consistency is not required, but availability is critical. Which database is most suitable?

Accepted Answer

Cloud Bigtable. Cloud Bigtable is optimized for high-throughput, low-latency reads and writes, and can serve as a leaderboard backend if row keys are designed properly. It offers eventual consistency, which is acceptable here. Cloud Spanner provides strong consistency but is more expensive and may have higher latency. Firestore is good for real-time updates but may not handle millions of concurrent updates easily. Memorystore (Redis) can also do leaderboards but is not a database for persistent storage; it's a cache.

Answer

Cloud Memorystore

Answer

Cloud Spanner

Answer

Cloud Firestore

Question 6

A company runs a batch process every night that loads data into BigQuery. They want to ensure that if the job fails, it is retried automatically up to 3 times. Which configuration should they use?

Accepted Answer

Cloud Composer (Airflow) tasks with retries.. Cloud Composer (Airflow) natively supports task-level retries via the `retries` parameter in task definitions, allowing you to specify up to 3 automatic retries on failure. This is the appropriate choice for orchestrating a batch process that loads data into BigQuery, as Airflow provides robust retry logic, dependency management, and monitoring for complex workflows.

Answer

Cloud Run jobs with --max-retries=3.

Answer

Cloud Scheduler with retry policy.

Answer

BigQuery load job with maximum retries setting.

Answer

Cloud Functions with error handling.

Question 7

Match each Google Cloud service to its primary purpose.

Accepted Answer

Cloud VPC: Isolated virtual network for GCP resources. These are core networking services in GCP. Cloud VPC provides isolated virtual networks, Cloud Load Balancing distributes traffic, Cloud CDN caches content at the edge, and Cloud NAT enables outbound internet for private instances. Common confusion: mixing up VPC and Load Balancing definitions, or CDN and NAT.

Answer

Cloud VPC: Distributes incoming traffic across multiple instances

Answer

Cloud CDN: Network address translation for private instances to access internet

Question 8

An organization uses Cloud SQL for MySQL in a production environment. They need to ensure high availability with automatic failover in case of a zonal failure. Which configuration should they use?

Accepted Answer

Create a regional Cloud SQL instance with automatic failover.. A regional Cloud SQL instance with automatic failover uses a primary and a standby zone within the same region, with synchronous replication between them. If the primary zone fails, Cloud SQL automatically promotes the standby to primary, ensuring high availability without data loss. This configuration meets the requirement for automatic failover during a zonal failure.

Answer

Create a read replica in a different region.

Answer

Export the database daily and import into a new instance if failure occurs.

Answer

Deploy Cloud SQL across multiple regions using cross-region replication.

Question 9

Refer to the exhibit. A Cloud Storage bucket has this IAM policy. What security recommendation should be made?

Accepted Answer

Remove the `allUsers` member and use signed URLs for public access.. The IAM policy grants `roles/storage.objectViewer` to `allUsers`, which makes the bucket's objects publicly readable by anyone on the internet. This is a security risk because it allows anonymous access without authentication or logging. The recommended practice is to remove the `allUsers` member and instead use signed URLs (which embed a time-limited access token) to grant temporary, controlled access to specific objects.

Answer

Change `allUsers` to `allAuthenticatedUsers` to allow only authenticated users.

Answer

Enable uniform bucket-level access and update the IAM policy.

Answer

Remove the `roles/storage.objectViewer` role binding entirely.

Question 10

You are responsible for incident management for a production service. You want to reduce manual toil during the initial response to common issues like high latency. What is the best approach?

Accepted Answer

Use Cloud Monitoring to trigger a Cloud Function that performs automated checks and rolls back the last deployment if latency spikes.. It directly reduces manual toil by automating the initial response to common issues like high latency. Cloud Monitoring triggers a Cloud Function that performs automated checks and, if latency spikes, rolls back the last deployment, eliminating the need for human intervention during the critical first response phase.

Answer

Set up Cloud Monitoring alerts with email notifications to the on-call engineer.

Answer

Create detailed runbooks and require the on-call to follow them step by step.

Answer

Enable Cloud Logging and set up a custom dashboard for the on-call.