Monitoring Azure Resources

Introduction to Azure Monitoring

Azure Monitoring provides a comprehensive solution for collecting, analyzing, and acting on telemetry from your cloud and on-premises environments. It helps you understand the performance and availability of your applications and infrastructure, identify problems, and optimize your resources.

Key capabilities include:

  • Collecting and aggregating logs and metrics.
  • Analyzing telemetry data to identify trends and diagnose issues.
  • Setting up alerts to notify you of critical conditions.
  • Visualizing your data through interactive dashboards.

Azure Monitor: The Foundation

Azure Monitor is the central service that enables comprehensive monitoring of your Azure and non-Azure resources. It collects and analyzes telemetry data from various sources, including:

  • Azure platform: Activity logs, resource logs.
  • Virtual machines and containers: Performance counters, event logs.
  • Applications: Application logs, traces, custom metrics.
  • Operating systems: System metrics.

Azure Monitor is composed of two core data types:

  • Metrics: Numerical values that describe some aspect of a system at a particular point in time.
  • Logs: Event-driven data that can be used for analysis, diagnostic, and auditing purposes.

Metrics in Azure Monitor

Metrics are lightweight and can support near real-time scenarios. They are useful for quickly identifying performance bottlenecks and potential issues. Azure Monitor collects metrics from a wide range of Azure services.

Metric Namespaces

Metric namespaces group related metrics for a particular Azure resource. For example, a virtual machine might have namespaces for CPU, memory, disk, and network usage.

Metric Dimensions

Dimensions are name-value pairs that categorize metrics. They allow you to filter and segment metric data. For instance, a network interface's metrics might be dimensioned by interface name or IP address.

Metric Queries

You can query metrics using the Azure portal, Azure CLI, Azure PowerShell, or programmatically via the Azure Monitor REST API.

Metrics are ideal for alerting on thresholds and for visualizing trends.

Logs in Azure Monitor

Logs are more verbose than metrics and can contain structured or unstructured data. They are essential for detailed troubleshooting, security analysis, and auditing.

Log Analytics

Log Analytics is a powerful tool within Azure Monitor for querying and analyzing log data. It provides a rich query language and visualization capabilities.

Kusto Query Language (KQL)

KQL is the query language used by Log Analytics. It's designed for exploring and analyzing large volumes of data efficiently.

Basic KQL structure:


TableName
| where ColumnName == "someValue"
| project AnotherColumn, Timestamp
| order by Timestamp desc

Query Examples

Here are some common KQL query examples:


// Get the last 100 records from the Syslog table
Syslog
| take 100

// Find all errors in the Application Insights logs for the last hour
requests
| where success == false
| where timestamp > ago(1h)

// Count the number of requests per API endpoint
requests
| summarize count() by operation_Name
| order by count_ desc
Logs are crucial for understanding the context of issues and for performing forensic analysis.

Alerts in Azure Monitor

Alerts notify you when specific conditions are detected in your monitoring data. You can create alert rules based on metrics or log queries.

Alerts can trigger various actions, including:

  • Sending email notifications.
  • Triggering Azure Functions or Logic Apps.
  • Calling webhooks.
  • Automatically resolving the issue (in some cases).
Configure alerts proactively to ensure you are notified of issues before they impact your users.

Dashboards

Azure Dashboards provide a flexible canvas for visualizing your monitoring data. You can pin charts, tables, and other visualizations from metrics and logs to a single dashboard for a consolidated view of your environment's health.

Application Insights

Application Insights is an extensible Application Performance Management (APM) service for developers and IT professionals. Use it to monitor your live applications, automatically detect anomalous behavior, and diagnose issues with minimal delay. It helps you understand how users interact with your app and what the performance of your backend services is.

Troubleshooting with Azure Monitor

When an issue arises, Azure Monitor is your primary tool for diagnosis:

  1. Check Alerts: Start by reviewing active alerts to identify potential problem areas.
  2. Examine Metrics: Look at key performance metrics (CPU, memory, network I/O, request rates) to see if they correlate with the issue.
  3. Analyze Logs: Query logs for detailed error messages, exceptions, or unusual activity patterns. Use KQL to filter and aggregate relevant information.
  4. Correlate Data: Combine insights from metrics, logs, and Application Insights to build a complete picture of the problem.
  5. Use VM Insights/Container Insights: For deeper insights into your VM and container performance and health.