Monitoring Azure Kubernetes Service (AKS)

Effective monitoring is crucial for maintaining the health, performance, and security of your Azure Kubernetes Service (AKS) clusters. This document outlines the key monitoring strategies and tools available for AKS.

Key Monitoring Areas

• Cluster Health: Monitoring the status of control plane components, nodes, and pods.
• Application Performance: Tracking the performance of your deployed applications, including request latency, error rates, and resource utilization.
• Resource Utilization: Observing CPU, memory, and network usage of nodes and pods.
• Security Events: Identifying suspicious activities and security-related events within the cluster.
• Cost Management: Monitoring resource consumption to optimize costs.

Azure Monitor for Containers

Azure Monitor for containers is the recommended solution for monitoring AKS clusters. It collects and analyzes telemetry data from your AKS environment, providing insights into performance and health.

• Container Insights: A feature within Azure Monitor that offers comprehensive monitoring of AKS. It provides:
  • Pre-built workbooks for visualizing key metrics.
  • Live data for near real-time cluster monitoring.
  • Alerting capabilities based on defined rules.
  • Integration with Log Analytics workspaces for deep diagnostics.

Enabling Container Insights

You can enable Container Insights during AKS cluster creation or for an existing cluster via the Azure portal or Azure CLI.

Using Azure CLI:

az aks enable-addons -a monitoring -n <your-aks-cluster-name> -g <your-resource-group>

Kubernetes Native Tools

AKS provides access to standard Kubernetes monitoring tools, which can be leveraged for detailed cluster introspection.

Metrics Server

Metrics Server is a cluster-wide aggregator of resource usage data. It's essential for the Horizontal Pod Autoscaler (HPA) and `kubectl top` commands.

Checking Pod CPU/Memory Usage:

kubectl top pods --all-namespaces

Checking Node CPU/Memory Usage:

kubectl top nodes

Kubernetes Dashboard

While not enabled by default, the Kubernetes Dashboard can be deployed to provide a web-based UI for managing and monitoring your cluster resources.

Logging

Centralized logging is critical for troubleshooting and auditing. AKS integrates seamlessly with Azure Log Analytics.

• Log Analytics Workspace: Collects logs from your AKS nodes and applications.
• Kube-state-metrics: Exposes metrics about the state of Kubernetes objects.
• Application Logging: Implement logging within your containerized applications using standard libraries and forward them to Log Analytics.

Alerting

Set up alerts in Azure Monitor to be notified of critical events:

• High CPU or memory utilization on nodes or pods.
• Pod restarts or failures.
• Application-specific error thresholds.
• Security-related anomalies.

Best Practices

• Enable Azure Monitor for Containers from the start.
• Configure appropriate retention policies for your Log Analytics workspace.
• Set up alerts for key performance indicators and potential issues.
• Use Kubernetes native tools for granular debugging.
• Implement application-level metrics and health checks.
• Regularly audit logs for security events and operational insights.

By leveraging these tools and strategies, you can ensure your AKS clusters are robust, performant, and secure.