Google ACE Ensuring Successful Operation of a Cloud Solution Practice Test 5 — 15 Questions

Question 1

You need to drain a GKE node for maintenance, ensuring that daemonsets and pods using emptyDir volumes are handled properly. Which command should you use?

Accepted Answer

kubectl drain NODE --ignore-daemonsets --delete-emptydir-data. kubectl drain with flags ignores daemonsets and deletes emptyDir pods.

Answer

kubectl taint nodes NODE key=value:NoSchedule

Answer

kubectl delete node NODE

Answer

kubectl cordon NODE && kubectl delete pods --all

Question 2

Your Cloud Run service has a new revision that you want to gradually shift traffic to. You want to send 10% of traffic to the new revision and 90% to the current one. Which TWO steps are required? (Choose TWO.)

Accepted Answer

Create the new revision by updating the service with a new image tag.. You first create the new revision (by updating the service) and then modify traffic percentages.

Answer

Set a new default URL for the new revision.

Answer

Delete the old revision.

Answer

Enable VPC ingress for the new revision.

Question 3

You are troubleshooting a Pub/Sub subscription that is not delivering messages promptly. Which THREE factors should you investigate? (Choose THREE.)

Accepted Answer

The subscription's backlog size. Common causes include backlog, subscriber latency, and ack deadlines.

Answer

The topic's retention duration

Answer

The message ordering key

Question 4

You need to be notified when the CPU utilization of any Compute Engine instance in your project exceeds 80% for 5 minutes. Which Cloud Monitoring feature should you use?

Accepted Answer

Metric threshold alerting policy. Metric threshold alerting policies allow you to set conditions based on metric values. When the condition (CPU > 80% for 5 minutes) is met, the alert fires and sends notifications via configured channels.

Answer

Uptime check

Answer

Log-based alert

Answer

Dashboard

Question 5

You are using Cloud Logging and want to export all logs from a specific Compute Engine instance to BigQuery for long-term analysis. You create a log sink with a filter for the instance's resource type and labels. What additional step is required to complete the export?

Accepted Answer

Create a BigQuery dataset and grant the log sink's service account the BigQuery Data Editor role. Log sinks require a destination. For BigQuery, the sink must be configured with the destination as a BigQuery dataset. You must create the dataset first, then specify it in the sink. The sink also needs appropriate permissions on the dataset.

Answer

Create a Cloud Pub/Sub topic and configure a push subscription

Answer

Create a Cloud Storage bucket as a staging location

Answer

Enable BigQuery's streaming buffer on the dataset

Question 6

You need to update a deployment in your GKE cluster from image version v1 to v2 gradually, ensuring that only a small percentage of pods run v2 initially. After the rollout, you want to verify the rollout status. Which commands should you use?

Accepted Answer

kubectl set image deployment/my-deployment my-container=gcr.io/my-project/my-image:v2 --record && kubectl rollout status deployment/my-deployment. Use kubectl set image to update the image, then kubectl rollout status to monitor the rollout. For gradual rollout, you can use kubectl rollout pause/resume or set maxSurge/maxUnavailable, but the question asks for the command to update and verify.

Answer

kubectl apply -f updated-deployment.yaml and kubectl rollout undo

Answer

kubectl edit deployment and kubectl rollout history

Answer

kubectl run my-deployment --image=gcr.io/my-project/my-image:v2 and kubectl get pods

Question 7

Your Cloud Run service is receiving a sudden spike in traffic. You want to ensure that the number of concurrent requests per container instance does not exceed 10 to avoid overloading the backend. Which configuration should you set?

Accepted Answer

Set --concurrency to 10. Cloud Run allows setting the maximum number of concurrent requests per container instance via the --concurrency flag or the concurrency field in the YAML. The default is 80; setting it to 10 limits each instance to 10 concurrent requests.

Answer

Set --timeout to 10 seconds

Answer

Set --max-instances to 10

Answer

Set --cpu-throttling to true

Question 8

You are investigating high latency in your application deployed on Compute Engine. You suspect a specific API call is taking longer than expected. Which Google Cloud tool should you use to analyze the latency of individual requests?

Accepted Answer

Cloud Trace. Cloud Trace provides distributed tracing, allowing you to see the latency of individual requests and identify bottlenecks. It captures trace spans from supported frameworks and services.

Answer

Cloud Debugger

Answer

Cloud Monitoring dashboards

Answer

Cloud Logging log explorer

Question 9

You need to resize a Compute Engine instance from n1-standard-4 to n1-highmem-8. The instance has a local SSD attached. What must you do before changing the machine type?

Accepted Answer

Stop the instance, change the machine type, then start the instance. To change the machine type, the instance must be stopped. Local SSDs preserve data only if the instance is not stopped or terminated; however, when you stop the instance, local SSD data is lost. The correct procedure is to stop the instance, change the machine type, and then start it. Data on local SSDs will be lost.

Answer

Take a snapshot of the local SSD

Answer

Change the machine type without stopping

Answer

Detach the local SSD

Question 10

Your team uses Cloud Logging to store application logs. You want to create a metric that counts the number of ERROR log entries per service. Which type of log-based metric should you create?

Accepted Answer

Counter metric. Log-based metrics can be counter metrics (count of log entries matching a filter) or distribution metrics. For counting occurrences, a counter metric is appropriate.

Answer

Distribution metric

Answer

Boolean metric

Answer

Gauge metric

Question 11

You are deploying a GKE cluster with node autoscaling enabled. The cluster runs batch jobs that are sensitive to startup latency. You notice that during scale-up, new nodes take several minutes to become ready. Which action can reduce the time it takes for new nodes to join the cluster?

Accepted Answer

Use a custom image with pre-installed dependencies. Using a custom image with pre-installed dependencies reduces the time needed for node initialization because the image already contains the required software, avoiding downloads during startup. This is especially beneficial for batch jobs.

Answer

Increase the initial node pool size

Answer

Set the --max-nodes-per-pool flag to a higher value

Answer

Enable cluster autoscaler with --enable-autorepair

Question 12

Your BigQuery query is taking longer than expected. You want to estimate the query cost before running it and get a preview of how many bytes will be processed. Which bq command should you use?

Accepted Answer

bq query --use_legacy_sql=false --dry_run 'SELECT ...'. The bq query command with the --dry_run flag (or --dry-run) will process the query and return the amount of data that would be scanned, without executing the query. This helps estimate cost and performance.

Answer

bq show --format=prettyjson mydataset.mytable

Answer

bq ls --format=prettyjson mydataset

Answer

bq query --use_legacy_sql=false --batch 'SELECT ...'

Question 13

You have a Pub/Sub subscription that is accumulating a backlog of messages. Which Cloud Monitoring metric should you alert on to detect this condition?

Accepted Answer

pubsub.googleapis.com/subscription/oldest_unacked_message_age. The Pub/Sub subscription's 'oldest_unacked_message_age' metric indicates how long the oldest unacknowledged message has been pending. A high value suggests a backlog that is not being processed.

Answer

pubsub.googleapis.com/subscription/sent_messages_count

Answer

pubsub.googleapis.com/subscription/unacked_messages_by_region

Answer

pubsub.googleapis.com/subscription/ack_message_count

Question 14

You need to set up log-based alerting in Cloud Logging to send notifications when a specific error pattern appears in your application logs. Which TWO components are required to accomplish this?

Accepted Answer

An alerting policy. To create a log-based alert, you need a log-based metric that counts the matching log entries, and an alerting policy that uses that metric. The metric is the source of the condition, and the policy defines when to notify.

Answer

A log sink

Answer

A Cloud Pub/Sub topic

Answer

An uptime check

Question 15

Your application running on Compute Engine is experiencing intermittent high latency. You need to diagnose the root cause. Which THREE tools or services should you use to gather data? (Choose 3)

Accepted Answer

Cloud Monitoring. Cloud Monitoring provides metrics and dashboards; Cloud Logging provides logs; Cloud Trace provides trace data for latency analysis. Together they cover metrics, logs, and traces for comprehensive troubleshooting.

Answer

Cloud Profiler

Answer

Cloud Debugger