Google PCA Managing Implementation and Ensuring Solution and Operations Reliability — 50 Questions

Question 1

A company wants to connect their on-premises data center to Google Cloud with a dedicated private connection that provides 99.99% availability and supports up to 100 Gbps bandwidth. They have a colocation facility near a Google Cloud region. Which connectivity option should they choose?

Accepted Answer

Dedicated Interconnect. Dedicated Interconnect provides direct physical connections between on-premises and Google Cloud, offering 10 Gbps or 100 Gbps per circuit and supporting multiple VLANs. For high availability, two circuits are recommended. Partner Interconnect is limited to 10 Gbps and relies on a service provider. HA VPN is over the public internet. Direct Peering does not provide SLA and is not recommended for production.

Answer

Partner Interconnect

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Direct Peering

Answer

HA VPN

Question 2

An organization needs to run a stateful application on Google Kubernetes Engine (GKE) where the nodes are fully managed by Google and the application workload SLAs are guaranteed. They want to minimize operational overhead. Which GKE mode should they use?

Accepted Answer

GKE Autopilot. GKE Autopilot manages the entire node infrastructure including node provisioning, scaling, and maintenance. It provides workload-level SLAs (e.g., 99.95% for pods). Standard mode requires the user to manage node pools.

Answer

GKE Standard with Cluster Autoscaler

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GKE Standard with node auto-provisioning

Answer

GKE Standard with sole-tenant nodes

Question 3

A financial services company runs a critical PostgreSQL database on Cloud SQL. They need to ensure automatic failover to a replica in another zone within the same region with minimal data loss. What configuration should they choose?

Accepted Answer

Configure a Cloud SQL HA instance with a failover replica in a different zone. Cloud SQL for PostgreSQL offers a High Availability (HA) configuration that provisions a standby instance in a different zone within the same region. Automatic failover is provided with synchronous replication to minimize data loss.

Answer

Use Database Migration Service to replicate to a second Cloud SQL instance

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Enable point-in-time recovery (PITR) and increase backup retention

Answer

Create a cross-region read replica and manually promote it on failure

Question 4

An engineer needs to create a custom dashboard in Cloud Monitoring to track the 99th percentile latency of their application over the last 7 days. Which type of metric should they use?

Accepted Answer

Distribution metric. Cloud Monitoring supports metric types: gauge, delta, and cumulative. Distribution metrics can be used to calculate percentiles. The 99th percentile latency is typically captured as a distribution metric.

Answer

Delta metric

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Cumulative metric

Answer

Gauge metric

Question 5

A team is implementing a canary deployment for a microservice on GKE using traffic splitting. They want to gradually shift 1% of traffic to a new version, monitor for errors, and then increase the percentage. Which tool or configuration should they use?

Accepted Answer

Use Cloud Deploy with a canary deployment strategy and Istio traffic splitting. Cloud Deploy supports canary deployments with traffic splitting via Istio or other service meshes. It allows gradual rollout and automated promotion based on criteria.

Answer

Configure a GKE Ingress with weighted backend services

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Deploy the new version to a separate namespace and use DNS weighting

Answer

Use Kubernetes Deployment with rolling update strategy

Question 6

An organization wants to receive alerts when their Cloud SQL instance's CPU utilization exceeds 80% for 5 minutes. They want to send the alert to both email and a Pub/Sub topic for further processing. What should they do?

Accepted Answer

Create a Cloud Monitoring alerting policy with a metric threshold condition on CPU utilization and add both email and Pub/Sub notification channels. In Cloud Monitoring, an alerting policy can have multiple notification channels (email, Pub/Sub, PagerDuty, SMS). The CPU utilization metric is available via the 'cloudsql.googleapis.com' metric type.

Answer

Configure a Cloud Scheduler job to check CPU utilization and publish to Pub/Sub

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Create a log-based alert for CPU utilization using Logging and route to email and Pub/Sub

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Use Cloud Functions to poll the Cloud Monitoring API every minute and send notifications

Question 7

An engineer needs to view the last 100 lines of a log file from a Compute Engine instance without leaving the Google Cloud Console. Which tool should they use?

Accepted Answer

Cloud Shell. Cloud Shell is an in-browser shell that comes pre-installed with gcloud and other tools. The engineer can SSH into the instance from Cloud Shell and use commands like 'tail' to view log lines.

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Cloud Logging in the Console

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Cloud Console's VM instances page

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Cloud SDK installed locally

Question 8

A company runs a critical application on Compute Engine and wants to automate recovery in case of a zone failure by redeploying instances in another zone. They have a startup script that configures the application. What is the simplest way to achieve zone failover?

Accepted Answer

Create a regional managed instance group (MIG) with autohealing. An instance group with autohealing and a health check can automatically recreate instances in another zone if the instance becomes unhealthy. However, for zone-level failure, a regional managed instance group (MIG) distributes instances across multiple zones and automatically rebalances if one zone fails.

Answer

Use a global load balancer with a backend service pointing to multiple zonal instance groups

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Set up a Cloud Scheduler to check instance health and create new instances via Cloud Functions

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Create a snapshot schedule and use Cloud Deployment Manager to recreate instances

Question 9

An engineering team wants to perform load testing on their new microservices-based application deployed on GKE. They need a tool that can simulate thousands of concurrent users, generate detailed performance metrics, and integrate with Cloud Monitoring. Which tool should they use?

Accepted Answer

Cloud Load Testing. Cloud Load Testing (formerly known as Cloud Load Testing) is a Google Cloud service that allows you to create load tests with simulated users and integrates with Cloud Monitoring for detailed metrics. Locust is an open-source alternative but lacks native integration with Cloud Monitoring.

Answer

Locust

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Apache JMeter

Answer

gcloud alpha loadtest

Question 10

A company needs to retain object versions in Cloud Storage for 90 days to protect against accidental deletion or modification. After 90 days, versions should be deleted. What feature should they enable?

Accepted Answer

Object lifecycle management with a rule to delete versions after 90 days. Object versioning in Cloud Storage keeps multiple versions of an object. Object lifecycle management can be configured to delete versions older than a specified number of days.

Answer

Object versioning only

Answer

Retention policy

Answer

Object holds

Question 11

A team is migrating a monolithic application to microservices on GKE. They want to gradually shift users to the new microservices version while keeping the old monolithic version running. They need to route a small percentage of users based on a cookie. Which traffic management approach should they use?

Accepted Answer

Use Istio VirtualService with match rules based on cookie and weighted destinations. Istio traffic management allows fine-grained routing based on HTTP headers, cookies, or other attributes. It supports traffic splitting and canary deployments with precise percentage control.

Answer

Use Kubernetes Services with multiple Deployments and manual scaling

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Configure an HTTP(S) load balancer with URL maps and backend services

Answer

Deploy two separate GKE clusters and use DNS-based traffic splitting

Question 12

An organization uses Cloud Spanner with a multi-region configuration to achieve 99.999% availability for their global user base. They notice an increase in write latency during peak hours. Which action would MOST effectively reduce write latency?

Accepted Answer

Add more nodes to the Spanner instance. In Cloud Spanner, write latency can be reduced by adding more nodes (increasing throughput) or optimizing schema. Adding nodes provides more compute and I/O capacity, reducing queuing and latency.

Answer

Use a stronger read consistency level

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Change from a multi-region to a single-region configuration

Answer

Enable follower reads

Question 13

A company wants to implement a disaster recovery (DR) strategy for their Cloud SQL for MySQL databases. They need to be able to recover to a specific point in time (within seconds) in case of accidental data deletion. Which TWO actions should they take? (Choose TWO.)

Accepted Answer

Enable binary logging (binlog). Point-in-time recovery (PITR) in Cloud SQL uses transaction logs to restore to any point in time within the backup retention period. Automated backups are required to enable PITR. Cross-region replication is for regional DR but not point-in-time.

Answer

Configure a failover replica in another zone

Answer

Create a cross-region read replica

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Export the database daily to Cloud Storage

Question 14

An engineer needs to troubleshoot a production issue on a Compute Engine instance. They suspect the instance is running out of memory. Which THREE actions should they take to diagnose the problem? (Choose THREE.)

Accepted Answer

SSH into the instance and run 'free -m' to check memory usage. Common troubleshooting involves checking instance metrics (Cloud Monitoring), analyzing logs (Cloud Logging), and connecting to the instance to run commands.

Answer

Increase the instance's memory by changing the machine type

Answer

Create a snapshot of the boot disk

Question 15

A company is designing a highly available architecture for a web application using Google Cloud. They need to ensure that the application remains available even if an entire Google Cloud region experiences an outage. Which THREE components should they include in their architecture? (Choose THREE.)

Accepted Answer

Cloud Spanner multi-region configuration. For multi-region high availability, use a global load balancer, deploy instances in multiple regions (e.g., via regional MIGs), and use a multi-region database like Cloud Spanner or cross-region replication.

Answer

Cloud SQL with a cross-region read replica

Answer

Cloud CDN

Question 16

Your company has a production Cloud SQL for PostgreSQL instance in us-central1 with automated backups enabled. You need to ensure that if the zone fails, the database automatically fails over to a standby in a different zone with minimal downtime. What should you do?

Accepted Answer

Configure the instance as a highly available (regional) instance.. Cloud SQL high availability (HA) configuration creates a standby instance in a different zone. The primary and standby use synchronous replication, and automatic failover occurs if the primary zone fails. Enabling deletion protection does not provide HA. Read replicas are for read scaling, not automatic failover. Automated backups alone do not provide failover.

Answer

Enable deletion protection on the instance.

Answer

Create a cross-region read replica and manually promote it during a failure.

Answer

Enable point-in-time recovery (PITR) and keep 30 days of transaction logs.

Question 17

An organization wants to connect their on-premises data center to Google Cloud with a dedicated 10 Gbps link. They require high availability and have budget for two physically diverse connections. Which solution should they choose?

Accepted Answer

Provision two Cloud Dedicated Interconnect connections from diverse peering points.. Cloud Dedicated Interconnect provides direct physical connections between on-premises and Google Cloud. For high availability, two separate circuits (each 10 Gbps or 100 Gbps) from diverse peering points are recommended. HA VPN is software-defined and lower bandwidth. Partner Interconnect uses a service provider but Dedicated Interconnect is preferred for dedicated bandwidth.

Answer

Use Partner Interconnect with a single 10 Gbps connection.

Answer

Configure a single Dedicated Interconnect connection and use Cloud VPN as backup.

Answer

Deploy a single HA VPN tunnel.

Question 18

Your team uses Cloud Deploy to manage canary deployments on GKE. You want to automatically roll back a release if the error rate increases by more than 5% within 10 minutes after the canary receives 10% of traffic. Which approach meets this requirement?

Accepted Answer

Use the Cloud Deploy rollout strategy with a canary phase and set the 'failurePolicy' to 'ROLLBACK' with a metric threshold.. Cloud Deploy supports canary deployments with automatic rollback based on Cloud Monitoring metrics. You can define a rollout strategy with a canary phase and attach an alert policy that triggers a rollback. Cloud Deploy integrates with Cloud Monitoring to watch metrics. Manual verification or Cloud Build does not provide automatic rollback based on metrics.

Answer

Configure a Cloud Build trigger to run a script that checks logs and rolls back if error rate exceeds threshold.

Answer

Set up a Cloud Monitoring alert with a notification to the SRE team and have them manually roll back.

Answer

Use GKE blue-green deployment with a manual verification step before switching traffic.

Question 19

You are designing a disaster recovery plan for a Cloud SQL for MySQL instance. The instance is in us-east1. You need to be able to recover the database to a specific second in time within the past 7 days in the event of a regional outage. What should you do?

Accepted Answer

Enable point-in-time recovery and create a cross-region read replica. If needed, promote and recover the replica to the desired point in time.. Cloud SQL point-in-time recovery (PITR) allows recovery to any second within the backup retention period. For regional disaster recovery, you need cross-region replicas. Enabling PITR on the primary and creating a cross-region replica (which also supports PITR) allows you to recover the replica to a specific point in time. Automated backups alone cannot restore to a specific second.

Answer

Enable automated backups and transaction log retention for 7 days. Restore the backup in a new instance in a different region.

Answer

Use Cloud SQL's built-in replication to create a cross-region replica, and enable failover. Failover automatically recovers to the latest transaction.

Answer

Export the database daily using gcloud sql export and store in Cloud Storage with versioning.

Question 20

A developer needs to view the last 100 lines of logs from a specific Compute Engine instance in real time to debug an application issue. Which command should they use?

Accepted Answer

gcloud logging read "resource.type=gce_instance AND resource.labels.instance_id=INSTANCE_ID" --limit=100 --freshness=1h. The gcloud logging read command can filter logs and tail them with the --freshness flag. gcloud compute instances get-serial-port-output retrieves serial console output, not application logs. gcloud app logs read is for App Engine. gcloud beta logging tail streams logs in real time.

Answer

gcloud beta logging tail

Answer

gcloud app logs read --limit=100

Answer

gcloud compute instances get-serial-port-output INSTANCE_NAME