Monitoring and Cost Management

Understanding how to monitor your Azure resources and manage costs is just as important as knowing how to build with them. Azure provides comprehensive tools for observability, alerting, and cost control.

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Azure Monitor

Azure Monitor is the unified monitoring platform for Azure. It collects, analyses, and acts on telemetry from your Azure resources, applications, and infrastructure.

Data Types

Type	Description	Example
Metrics	Numerical time-series data	CPU utilisation, request count, latency
Logs	Structured event records	Application errors, audit events, resource changes
Traces	Distributed request tracing	End-to-end request flow across services

Key Components

Component	Purpose
Metrics Explorer	Visualise and analyse metrics in real time
Log Analytics	Query logs using Kusto Query Language (KQL)
Alerts	Trigger notifications or actions based on conditions
Dashboards	Custom visualisations of metrics and logs
Workbooks	Interactive reports combining text, queries, and visualisations

Alerts

Azure Monitor alerts notify you when conditions are met:

Alert Type	Triggers On
Metric alert	A metric crosses a threshold (e.g., CPU > 80%)
Log alert	A log query returns results
Activity log alert	A specific Azure operation occurs (e.g., VM deleted)

When an alert fires, it can:

• Send an email or SMS
• Call a webhook
• Trigger an Azure Function or Logic App
• Create an ITSM ticket

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Application Insights

Application Insights is an extension of Azure Monitor for application performance management (APM):

• Request tracking — response times, failure rates, dependency calls
• Exception logging — stack traces and diagnostic data
• Live metrics — real-time telemetry during active investigation
• Availability tests — synthetic tests that ping your app from Azure locations worldwide
• Application Map — visual representation of your application's components and dependencies

You add the Application Insights SDK (or enable auto-instrumentation) to your application code.

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Azure Activity Log

The Activity Log records control-plane operations on Azure resources:

• Who performed the operation
• What operation was performed (e.g., create VM, delete resource group)
• When it occurred
• Status (succeeded, failed, started)

The Activity Log is retained for 90 days. For longer retention, send it to a Log Analytics workspace or storage account.

Example KQL Query

AzureActivity
| where OperationNameValue == "Microsoft.Compute/virtualMachines/delete"
| where ActivityStatusValue == "Success"
| project TimeGenerated, Caller, ResourceGroup
| order by TimeGenerated desc

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Azure Cost Management

How Azure Billing Works

Azure costs are based on resource consumption:

Entra ID Tenant
  |
  |-- Billing Account
        |
        |-- Billing Profile
              |
              |-- Invoice Section
                    |
                    |-- Subscription A (resources billed here)
                    |-- Subscription B

Azure Pricing Calculator

The Pricing Calculator (azure.microsoft.com/pricing/calculator) lets you estimate costs before deploying: