25 of 100 questions · Page 2/2 · Ace Ensuring Operation topic · Answers revealed
A site reliability engineer needs to be notified immediately when the error rate of a production microservice exceeds 5% over a 5-minute window. Which type of alerting policy should be used?
A metric threshold alert evaluates a metric against a threshold and is ideal for this use case.
Why this answer
A metric threshold alert triggers when a metric crosses a threshold. This scenario requires tracking the error rate metric and alerting when it exceeds 5%.
Content matching allows you to specify a regex or substring to check in the response body.
Why this answer
Uptime checks can validate response content using content matching.
Your GKE cluster is running an older version of Kubernetes. You need to upgrade the cluster's control plane and node pools. Which two steps should you perform? (Choose two.)
The control plane must be upgraded first.
Why this answer
Upgrading a GKE cluster involves upgrading the cluster (control plane) first using gcloud container clusters upgrade, and then upgrading node pools separately (or they can be auto-upgraded). You cannot upgrade nodes without upgrading the control plane first. Draining nodes is not a step for upgrading, it's for maintenance.
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?
Correct: a counter metric counts log entries that match the filter (e.g., severity=ERROR).
Why this answer
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.
You are managing a Cloud Run service that has two revisions: v1 (serving 100% traffic) and v2 (new revision). You want to shift 10% of traffic to v2 gradually. Which TWO steps should you take? (Choose two.)
This command updates traffic to send 10% to v2, leaving the rest (90%) to the latest ready revision (v1 if no other revisions defined).
Why this answer
To split traffic, you need to create a traffic configuration that assigns percentages to revisions. Options B and D are correct.
Your GKE cluster has a node pool that you want to enable autoscaling on. The initial node count is 3, and you want the cluster to scale between 1 and 10 nodes. Which command should you use?
This command correctly updates the node pool with autoscaling and min/max nodes.
Why this answer
The correct command is gcloud container node-pools update with --enable-autoscaling and the min and max node flags. The cluster name and region/zone are required.
You need to load a CSV file from Cloud Storage into an existing BigQuery table. Which bq command should you use?
This correctly loads the CSV file into the table.
Why this answer
The bq load command loads data into a BigQuery table. You specify the source format (CSV) and the location of the file in Cloud Storage.
You notice that a deployment in your GKE cluster is running an outdated image. You need to update the deployment to use the new image 'gcr.io/my-project/my-app:v2'. Which kubectl command should you use?
This is the correct syntax: kubectl set image deployment/<name> <container>=<image>.
Why this answer
To update the image of a deployment, use 'kubectl set image' specifying the deployment name and the container name:tag.
You need to drain a GKE node for maintenance. The node is running a DaemonSet and some pods with emptyDir volumes. Which kubectl command should you use to safely drain the node without causing errors?
These flags handle DaemonSets and emptyDir volumes, allowing the drain to complete.
Why this answer
The kubectl drain command with --ignore-daemonsets and --delete-emptydir-data flags safely evicts pods while ignoring DaemonSets (which are managed by the node) and allowing deletion of pods with emptyDir volumes.
You want to create a monitoring dashboard that shows a time-series chart of CPU utilization for a specific Compute Engine instance. Which THREE components do you need to configure? (Choose three.)
Aggregation is needed for the time series.
Why this answer
In Cloud Monitoring, to create a chart you need to select a metric, a resource, and a time aggregation function.
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.)
Updating the service creates a new revision.
Why this answer
You first create the new revision (by updating the service) and then modify traffic percentages.
You have a Compute Engine VM that is running a critical application. You need to change its machine type from n1-standard-4 to n2-standard-8. What is the correct procedure?
This is the correct procedure: stop, change machine type, start.
Why this answer
To change the machine type of a VM, you must stop the instance first, then use the gcloud compute instances set-machine-type command, and finally start the instance again.
A Cloud Run service named 'my-service' is currently serving 100% traffic to revision 'rev1'. You deploy a new revision 'rev2' and want to gradually shift traffic so that rev2 receives 10% of requests. Which command should you use?
This correctly sends 10% to rev2 and 90% to rev1.
Why this answer
gcloud run services update-traffic allows you to set traffic percentages per revision. The syntax is --to-revisions=REVISION=PERCENTAGE.
You are troubleshooting a Pub/Sub subscription that is not receiving messages as fast as they are published. You want to check if there is a backlog of unacknowledged messages for the subscription. What should you use?
This metric directly indicates the backlog.
Why this answer
Cloud Monitoring has a metric for Pub/Sub subscription backlog (oldest unacknowledged message age or num_undelivered_messages).
You need to query logs in Cloud Logging to find errors from a specific Compute Engine instance. The instance ID is 'my-instance'. Which query language filter should you use?
Correctly filters for GCE instance and severity ERROR or higher.
Why this answer
The filter should specify resource.type and resource.labels.instance_id.
You need to create a log-based metric that counts the number of errors in your application logs. What must you do first in Cloud Logging?
You define a filter to select the logs, then create the metric based on that filter.
Why this answer
In Cloud Logging, a log-based metric is based on a filter. You define the filter using the logging query language to match the logs you want to count, then create the metric from that filter.
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?
Correct: concurrency limits the number of simultaneous requests per container instance.
Why this answer
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.
An engineer needs to enable autoscaling on an existing node pool in a GKE cluster. Which command should they use?
Why this answer
'gcloud container node-pools update' with '--enable-autoscaling' enables autoscaling. 'gcloud container clusters update' updates cluster-level settings, not node pools. 'kubectl autoscale' is for workloads, not node pools. 'gcloud compute instance-groups' is not used for GKE node pools.
A DevOps team wants to be notified in Slack when a specific error log appears in Cloud Logging. They set up a log-based alert with a notification channel to a Slack webhook. However, notifications are not arriving. What is the most likely cause?
Why this answer
Slack webhooks require a Pub/Sub topic as an intermediary for Cloud Monitoring notifications. Direct Slack integration via webhook is not supported; you must use a Pub/Sub topic with a push subscription to Slack.
You need to monitor the uptime of an external HTTPS endpoint that is critical to your application. Which Google Cloud service should you use to create an uptime check?
Cloud Monitoring includes uptime checks for verifying endpoint availability.
You need to create a snapshot of a persistent disk attached to a running Compute Engine instance. The disk is used by a production database; you want minimal impact. What should you do?
Stopping ensures data consistency with minimal risk.
Why this answer
Creating a snapshot of a disk in use is possible, but for data consistency, it's recommended to stop the instance or at least freeze the filesystem. However, the question says 'minimal impact', so the best practice is to stop the instance. But the correct answer reflects that snapshots can be taken from attached disks, but for database consistency, stop is recommended.
Let's choose the safer answer: stop the instance.
You are troubleshooting a slow application that uses multiple microservices. You suspect a particular service is causing high latency. Which TWO Google Cloud tools should you use to identify the root cause? (Select 2)
Metrics and dashboards can show latency per service.
Why this answer
Cloud Trace traces requests across services to pinpoint latency, and Cloud Monitoring can show metrics like request latency and error rates.
You are configuring a log sink to export logs to Cloud Storage for compliance. Which TWO permissions are required for the sink's destination bucket? (Choose TWO.)
Required to view and manage the objects.
Why this answer
The sink needs storage.objectCreator and storage.objectViewer to write and manage objects.
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?
Correct: metric threshold alerting policies are designed for conditions like CPU > 80% for 5 minutes.
Why this answer
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.
A Cloud Run service needs to be updated to increase CPU and memory limits. Which command should the engineer use?
Why this answer
'gcloud run services update' allows updating service configuration including CPU and memory. 'gcloud run revisions update' does not exist; revisions are immutable. 'gcloud run deploy' is used for initial deployment or updating to a new revision, but 'update' is the correct command for modifying an existing service's configuration.
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