PCDOE Practice Test 18 — 15 Questions

Question 1

A company uses Cloud Monitoring to set up alerting for their production system. They want to reduce alert fatigue while ensuring critical issues are caught quickly. Which two strategies should they implement? (Select TWO)

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

Accepted Answer

Use notification channels with escalation policies. Option A is correct because Cloud Monitoring notification channels can be paired with escalation policies so that alerts are routed to the right on-call responder and only escalate to additional recipients (e.g., via SMS or phone) when the issue is not acknowledged within a defined time, reducing noise while ensuring critical issues reach someone quickly. Option C is correct because alert aggregation and deduplication group related incidents (for example, multiple time series from the same service or incident) into a single notification, preventing duplicate pages and lowering alert fatigue without suppressing genuine critical signals. Option B is wrong because setting low thresholds makes alerts fire more often on minor or transient deviations, which increases false positives and worsens alert fatigue. Option D is wrong because disabling alerts during off-hours can cause critical production issues to go undetected, contradicting the goal of catching critical issues quickly. Option E is wrong because creating separate alerts for every microservice multiplies notification volume and fragments incident context, which increases rather than reduces alert fatigue.

Answer

Use low threshold values to catch issues early

Answer

Disable alerts during off-hours

Answer

Set up separate alerts for each microservice

Question 2

A company uses a Shared VPC and wants to enforce a set of firewall rules across all projects in a folder. They want these rules to be immutable by project owners. Which approach should they use?

Accepted Answer

Use hierarchical firewall policies at the folder level.. Hierarchical firewall policies allow you to enforce firewall rules at the folder level, which are inherited by all projects within that folder. These policies are immutable by project owners because they are managed at the folder level, not the project or VPC level, and cannot be overridden or deleted by lower-level roles unless explicitly granted permission.

Answer

Use network tags and service accounts to enforce rules.

Answer

Use organization policy constraints to prevent project owners from modifying firewall rules.

Answer

Create firewall rules at the VPC level and assign them to the folder.

Question 3

Match each Cloud Monitoring metric type to its description.

Accepted Answer

Gauge: A metric that measures a value at a specific point in time.. The correct matches are: Gauge measures a point-in-time value, Cumulative measures accumulated value over time, and Delta measures rate of change. Common confusions include swapping definitions between gauge and cumulative, or misunderstanding delta as cumulative.

Answer

Gauge: A metric that measures an accumulated value over time.

Answer

Cumulative: A metric that measures a value at a specific point in time.

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Delta: A metric that measures an accumulated value over time.

Question 4

Match each Google Cloud deployment strategy to its description.

Accepted Answer

Blue/green deployment: Running two identical environments, only one serves traffic at a time.. Blue/green uses two environments, canary uses a small user subset, rolling updates gradually. Swapping definitions is a common distractor.

Answer

Blue/green deployment: Gradually replacing instances of the current version with the new one.

Answer

Canary deployment: Running two versions side-by-side and routing users based on test groups.

Answer

Rolling deployment: Switching traffic between two separate environments.

Question 5

Match each SRE term to its description.

Accepted Answer

SLI: A carefully defined quantitative measure of some aspect of the level of service.. The correct matches are: SLI with a quantitative measure, SLO with a target value, SLA with a contract including consequences, and Error Budget with remaining unreliability. Common confusions include swapping Error Budget with SLI or confusing SLO with SLA.

Answer

SLI: The acceptable amount of unreliability remaining before the SLO is violated.

Answer

SLO: A contract with users that includes consequences.

Question 6

A company is migrating a batch processing workload to Google Cloud. The workload is CPU-intensive and runs for a few hours each day. Which Compute Engine machine family should they choose to optimize performance and cost?

Accepted Answer

Compute-optimized (C2/C2D). A is correct because the workload is CPU-intensive and runs for a few hours each day, which is a sustained, compute-bound task. Compute-optimized machines (C2/C2D) are designed specifically for high-performance computing (HPC) and batch processing, offering the highest ratio of vCPU to memory and the fastest single-threaded performance on Google Cloud. This minimizes runtime and cost per job compared to general-purpose or burstable families.

Answer

Burstable (T2D)

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GPU-accelerated (A2)

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Memory-optimized (M2)

Question 7

An application running on GKE experiences high tail latency. The team is optimizing performance. Which THREE techniques should they consider? (Choose three.)

Accepted Answer

Use pod anti-affinity to spread pods across nodes. Option A is correct because pod anti-affinity spreads replicas across different nodes, preventing multiple latency-sensitive pods from competing for the same node's CPU, memory, and network resources, which reduces tail latency caused by noisy-neighbor effects. Option B is correct because setting accurate resource requests and limits ensures pods get guaranteed CPU/memory and are not throttled or evicted, directly avoiding resource contention that inflates tail latency. Option E is correct because scaling stateless services horizontally with more replicas distributes traffic and load, reducing per-pod queueing and improving tail latency under high concurrency. Option C is not correct because injecting an Istio sidecar adds a proxy hop and overhead that can increase latency rather than reduce it, and it is not a performance optimization technique. Option D is not correct because pod affinity packs pods onto the same node, which increases resource contention and worsens tail latency, the opposite of what is needed.

Answer

Enable Istio sidecar injection for all pods

Answer

Use pod affinity to pack pods on same node

Question 8

An organization wants to enforce that all Compute Engine VMs use only specific machine families (e.g., N2, C2). Which mechanism should they use?

Accepted Answer

Organization policy with compute.restrictComputeEngineMachineTypes. Organization policies in Google Cloud allow administrators to enforce constraints on resources across the entire hierarchy. The `compute.restrictComputeEngineMachineTypes` constraint specifically limits which machine families (e.g., N2, C2) can be used when creating Compute Engine VMs, making it the correct mechanism for this requirement.

Answer

IAM deny policies

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Quota management

Answer

Folders with different owners

Question 9

Which TWO actions can reduce startup latency for a Cloud Run service?

Accepted Answer

Optimize the container image to reduce size.. Option C is correct because a smaller container image reduces the time Cloud Run needs to pull the image and start the container, directly lowering cold-start latency. Option E is correct because setting a minimum number of instances keeps at least one instance warm and ready, so requests avoid cold starts entirely. Option A is incorrect because deploying separate regional services affects availability and locality, not the startup time of a given instance. Option B is incorrect because the maximum instances limit only caps horizontal scaling and does not make individual instances start faster. Option D is incorrect because container concurrency controls how many requests a single instance handles simultaneously, which affects throughput and resource use rather than startup latency.

Answer

Use a regional Cloud Run with separate service per region.

Answer

Increase the maximum instances limit.

Answer

Increase the container concurrency setting.

Question 10

A company serves static assets (images, CSS) to global users. Users in distant regions experience slow load times. Which service should they use to optimize delivery?

Accepted Answer

Cloud CDN. Cloud CDN (Content Delivery Network) caches static assets (images, CSS) at edge locations worldwide, reducing latency for distant users by serving content from a nearby point of presence (PoP). This directly addresses slow load times caused by geographic distance, as the origin server is no longer the sole source of delivery.

Answer

Cloud Load Balancing

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Cloud NAT

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Cloud Armor

Question 11

A financial services company runs a real-time trading application on GKE with 10 microservices. The application uses Cloud Spanner as the database. Recently, the team noticed increased latency during peak trading hours. Cloud Monitoring shows high CPU utilization on the Spanner nodes (averaging 80%) and increased locking contention. The team has already added secondary indexes and tuned queries. The application's latency budget is 50ms for writes and 20ms for reads. The team must reduce latency while maintaining strong consistency and meeting the budget. What should they do?

Accepted Answer

Increase the number of Spanner nodes to reduce contention and CPU load. Increasing the number of Spanner nodes directly addresses the root cause: high CPU utilization (80%) and locking contention. More nodes distribute the read/write load, reducing per-node CPU and contention, which lowers latency. This maintains strong consistency and meets the 50ms write / 20ms read budget without architectural changes.

Answer

Change the application to use eventual consistency for read operations

Answer

Migrate the database to Cloud Bigtable for higher throughput

Answer

Implement a write buffer using Cloud Pub/Sub and batch writes to Spanner

Question 12

A developer wants to trigger a Cloud Build execution whenever a pull request is created against the main branch in Cloud Source Repositories. Which Cloud Build trigger configuration should be used?

Accepted Answer

Event: pull request on branch ^main$. The correct trigger configuration is an event of type 'pull request' on the branch matching ^main$. Cloud Build supports pull request triggers that fire when a PR is created or updated against a specific branch, allowing automated checks or builds before merge. This directly addresses the requirement to trigger on PR creation against the main branch.

Answer

Event: push on branch ^main$

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Event: push on tag

Answer

Event: manual invocation

Question 13

Refer to the exhibit. Your team deployed a new revision to Cloud Run. After deployment, error rates increased. You want to roll back to the previous revision, which is still serving. Which command should you use?

Accepted Answer

gcloud run services update-traffic my-service --to-revisions=my-service-00001-caz=100. `gcloud run services update-traffic` allows you to precisely control traffic splitting between revisions. By setting `--to-revisions=my-service-00001-caz=100`, you direct 100% of incoming requests to the previous revision, effectively rolling back without deleting the current revision. This command is the standard method for traffic-based rollbacks in Cloud Run.

Answer

gcloud run services rollback my-service

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gcloud run revisions delete my-service-00002-caw

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gcloud run deploy my-service --image gcr.io/my-project/my-image:v1

Question 14

A company is migrating from Jenkins to Cloud Build for their CI/CD pipeline. They have a large Java monorepo with multiple modules that take over 2 hours to build and test sequentially. They want to reduce build time by running module builds in parallel. The current Jenkins pipeline uses a single Jenkinsfile that builds all modules. They have a Cloud Build config that runs 'mvn clean package' for the entire project, which is slow. They have a 2-hour Cloud Build timeout. The architecture requires that some modules depend on others. Which approach should they take to minimize build time while correctly handling dependencies?

Accepted Answer

Create a single build config that defines parallel steps for independent modules, using 'waitFor' to sequence dependent modules, and uses Maven's incremental compilation with caching.. The correct approach is a single Cloud Build config that defines parallel steps for independent modules, uses waitFor to sequence dependent modules, and leverages Maven incremental compilation with caching. This minimizes build time by parallelizing independent work while respecting the dependency graph, and caching avoids rebuilding unchanged modules. It stays within the 2-hour timeout by reducing total wall-clock time.

Answer

Break the monolith into separate Cloud Build triggers per module and run them independently on every push.

Answer

Use a build step that runs 'mvn -pl moduleA,moduleB -am' to build only changed modules and their dependencies.

Answer

Increase the Cloud Build timeout to 4 hours and keep a single build step.

Question 15

During a Cloud Build execution, the step fails with 'Error: could not find a valid 'Dockerfile' in context '.''. The build configuration file is located in a subdirectory called 'build/' and the Dockerfile is in the root of the repository. How should the team fix this?

Accepted Answer

Specify the 'dir' field in the build step to point to the root.. The Cloud Build step's `dir` field explicitly sets the working directory for the step. By specifying `dir: '.'` (or the repository root), Cloud Build will look for the Dockerfile in the root context, even though the build configuration file (`cloudbuild.yaml`) resides in the `build/` subdirectory. This ensures the Docker build context points to the correct location where the Dockerfile exists.

Answer

Create a symbolic link.

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Move the Cloud Build configuration file to the root.

Answer

Use the 'substitutions' to change context.