Cloud Monitoring: ACE Exam Study Guide (2026)

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1. Cloud Monitoring Overview

Cloud Monitoring provides visibility into the performance, uptime, and overall health of your applications and infrastructure.

• Key Characteristics:
  • Full Stack: Monitors GCP services, AWS, and on-premises resources.
  • Integrated: Collects metrics, events, and metadata from Cloud Logging, Trace, and Debugger.
  • Real-time: Provides a real-time dashboarding and alerting system.

2. Metrics and Time Series

• System Metrics: Automatically collected from GCP services (e.g., CPU, Disk I/O).
• Custom Metrics: Metrics you define and send to Monitoring via the API.
• Log-based Metrics: Metrics derived from the content of your logs in Cloud Logging.
• Time Series: The fundamental data structure in Monitoring, representing data points over time.

Common Metric Types

Metric Types by Resource

3. Dashboards, MQL, and Metrics Explorer

Dashboards provide a visual representation of your metrics.

• Google Cloud Dashboards: Pre-defined dashboards created automatically.
• Custom Dashboards: Dashboards you create to monitor specific aspects of your application.
• MQL (Monitoring Query Language): A powerful language used to create complex charts and data transformations.

MQL Example

fetch gce_instance
| metric 'compute.googleapis.com/instance/cpu/utilization'
| filter resource.zone == 'us-east1-b'
| align rate(1m)
| every 1m
| group_by ['instance_name'], mean(val())

Dashboard Types

Metrics Explorer

A tool for ad-hoc analysis of any metric:

• Select from hundreds of available metrics
• Filter by resource, zone, or labels
• Build custom charts without saving
• Export to dashboards or use in MQL queries

4. Alerting Policies

Alerting policies notify you when specific conditions are met.

Alerting Workflow

Define Condition (metric threshold)
         ↓
Set Duration (e.g., "for 5 minutes")
         ↓
Configure Notification Channel (email, SMS, Slack, PagerDuty, Webhook)
         ↓
Add Documentation (runbook links, escalation contacts)
         ↓
Alert Triggered → Incident Created

Alerting Policy Types

• Uptime Checks vs Alerting Policies:

  • Uptime Checks: Test availability of a service (HTTP/HTTPS/TCP)
  • Alerting Policies: React to metric conditions or uptime failures

• Components of an Alerting Policy:

  • Conditions: What triggers the alert (e.g., “CPU utilization > 80% for 5 minutes”).
  • Notification Channels: How you are notified (Email, SMS, Slack, PagerDuty, Webhooks).
  • Documentation: Instructions or links to playbooks included in the alert.

• Incident Management: When an alert is triggered, an incident is created for tracking and resolution.

5. Synthetic Monitoring (2026 Update)

Synthetic monitoring replaces traditional uptime checks with more complex, programmable checks.

• Protocols: Supports HTTP, HTTPS, and TCP.
• Custom Scripts: Use Node.js or Python scripts to simulate complex user journeys (e.g., “Login -> Add to Cart -> Checkout”).
• Global Probes: Checks are performed from multiple regions around the world.
• Alerting Integration: Notify you if a synthetic check fails or exceeds latency thresholds.

In Cloud Monitoring, you create an uptime check specifying the URL, protocol (HTTP/HTTPS/TCP), frequency, and locations to check from. If the service fails to respond from multiple locations, an alert can be triggered.

6. Groups and Resources

Groups allow you to organize and monitor sets of resources together.

• Criteria: You can define groups based on names, tags, labels, or regions.
• Use Case: Monitor all web servers in the us-east1 region as a single entity.

6.1 SLOs and SLIs

Service Level Objectives (SLOs) and Service Level Indicators (SLIs) are key reliability concepts:

• SLO Monitoring: Cloud Monitoring can create alerting policies based on SLO burn rate to notify you before SLOs are breached.

7. Essential gcloud Commands

• List Metrics: gcloud monitoring metric-descriptors list
• Create a Dashboard: gcloud monitoring dashboards create --config-from-file=[DASHBOARD_JSON]
• List Alerting Policies: gcloud monitoring policies list

8. Exam Tips

• Log-based Metric vs. System Metric: Use log-based metrics for counting log events. Use system metrics for performance data.
• Ops Agent: For “inside-the-OS” metrics like Memory usage and internal process stats, the Ops Agent must be installed on VMs.
• Synthetic Monitoring: If a question asks for testing a multi-step user flow from multiple regions, choose Synthetic Monitoring.
• Alerting vs. Uptime Checks: Uptime checks test availability; alerting policies react to metric conditions.
• Metrics Explorer: Use for ad-hoc analysis; dashboards are for persistent monitoring views.

9. Security and IAM

• IAM Roles:
  • roles/monitoring.admin: Full control over all Monitoring resources
  • roles/monitoring.editor: Create and modify dashboards, alerts, uptime checks
  • roles/monitoring.viewer: View metrics and dashboards (read-only)
  • roles/monitoring.alertPolicyViewer: View alerting policies
  • roles/monitoring.alertPolicyEditor: Create and modify alerting policies

10. GCP Observability Tools Comparison