Monitoring Azure Kubernetes Service (AKS)

Effective monitoring is crucial for understanding the health, performance, and security of your Azure Kubernetes Service (AKS) clusters. This article explores the key monitoring tools and strategies available for AKS, helping you to proactively identify and resolve issues.

Key Monitoring Components in AKS

AKS integrates with Azure's comprehensive monitoring services, providing deep insights into your cluster's operations. The primary services you'll leverage are:

Azure Monitor: The foundational monitoring service for Azure resources. It collects, analyzes, and acts on telemetry from your AKS cluster.
Container Insights: A feature within Azure Monitor specifically designed for monitoring containerized applications and their underlying hosts.
Azure Log Analytics: The underlying engine for collecting and querying logs from various sources, including AKS.
Prometheus and Grafana: Open-source tools that are widely adopted in the Kubernetes ecosystem for metrics collection and visualization. AKS can integrate with these.

Leveraging Container Insights

Container Insights provides a rich set of dashboards and alerts for your AKS clusters. It automatically collects:

Node and Pod Metrics: CPU, memory, disk, and network utilization.
Cluster Performance: Information on cluster state, resource requests/limits, and scheduling status.
Application Logs: Logs from containers running within your cluster.
Kubernetes Audit Logs: Records of operations performed on your cluster.

Enabling Container Insights

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


az aks enable-monitoring --resource-group  --name  --workspace-id

Accessing Container Insights Data

Once enabled, you can access the Container Insights dashboards within the Azure portal under your AKS cluster's resource menu. You can also query the collected logs directly in Log Analytics.

Tip: Customizing Workbooks

Container Insights leverages Azure Monitor Workbooks. You can customize existing workbooks or create your own to visualize specific metrics and logs relevant to your applications.

Using Prometheus and Grafana

For those who prefer or already use Prometheus and Grafana, AKS offers integration options:

Prometheus Add-on: AKS can deploy and manage a Prometheus instance within your cluster.
Grafana Integration: You can configure Grafana to scrape metrics from the deployed Prometheus instance and create custom dashboards.

Benefits of Prometheus/Grafana

This approach offers:

Flexibility: Full control over metrics collection and dashboarding.
Ecosystem Compatibility: Seamless integration with existing Kubernetes monitoring stacks.
Community Support: Access to a vast community and numerous pre-built Grafana dashboards for Kubernetes.

                
# Example of enabling Prometheus using Helm (if not using AKS add-on)
helm install prometheus prometheus-community/prometheus --namespace monitoring --create-namespace

Alerting Strategies

Proactive alerting is key to maintaining cluster health. Azure Monitor allows you to create alert rules based on metrics and logs. Common alert scenarios include:

High CPU or memory utilization on nodes or pods.
Pods entering a failed state.
Node unavailability.
Application-specific error rates exceeding a threshold.
Security-related events detected in audit logs.

Pro Tip: Action Groups

Configure Azure Monitor Action Groups to notify your team via email, SMS, or trigger automated actions like running an Azure Function or Webhook when an alert fires.

Best Practices for AKS Monitoring

Define SLOs/SLIs: Clearly define your Service Level Objectives (SLOs) and Service Level Indicators (SLIs) for your applications and cluster.
Monitor Key Metrics: Focus on essential metrics like CPU/memory usage, pod restarts, API server latency, and etcd health.
Centralize Logging: Ensure all application and cluster logs are sent to a central location like Log Analytics for easier analysis and correlation.
Regularly Review Dashboards: Make it a habit to review your monitoring dashboards to spot trends and potential issues before they impact users.
Implement Health Probes: Configure liveness and readiness probes for your application pods to ensure Kubernetes can manage their lifecycle effectively.
Secure Your Monitoring Data: Ensure your Log Analytics workspace and any other monitoring tools are secured with appropriate access controls.

By implementing a robust monitoring strategy, you can ensure the reliability, performance, and security of your applications running on Azure Kubernetes Service.