Manage Azure Kubernetes Service (AKS) Clusters

Last Updated: October 26, 2023 | Author: Microsoft Docs

This document provides a comprehensive guide to managing your Azure Kubernetes Service (AKS) clusters. Effective management is crucial for ensuring the availability, performance, and security of your containerized applications.

Core Management Tasks

Monitoring Cluster Health and Performance

Regularly monitoring your AKS cluster is essential for identifying and resolving potential issues before they impact your applications. Azure Monitor for containers provides deep insights into the performance of your container workloads.

Metrics: Track CPU, memory, and network utilization of your nodes and pods.
Logs: Collect and analyze container logs for debugging and troubleshooting.
Alerting: Set up alerts for critical performance thresholds or error conditions.

You can integrate Azure Monitor with Azure Kubernetes Service through the Azure portal or using command-line tools.

Scaling Your Cluster

As your application demands change, you can scale your AKS cluster to accommodate increased or decreased workloads. Scaling involves adjusting the number of nodes in your node pools or configuring autoscaling.

Manual Scaling: Adjust the node count in a node pool directly via the Azure portal or Azure CLI.
Cluster Autoscaler: Automatically adjusts the number of nodes based on pod resource requests and pending pods.

To configure the Cluster Autoscaler, you can use the following Azure CLI command:

az aks nodepool update \
    --resource-group myResourceGroup \
    --cluster-name myAKSCluster \
    --name nodepool1 \
    --enable-cluster-autoscaler \
    --min-count 1 \
    --max-count 5

Upgrading AKS Clusters

Keeping your AKS cluster updated with the latest Kubernetes versions and security patches is vital. AKS supports in-place upgrades of both the control plane and node pools.

Important considerations:

Always back up your critical data before performing an upgrade.
Test upgrades in a staging environment first.
Plan for potential downtime during the upgrade process.

You can view available upgrade versions using:

az aks get-upgrades --resource-group myResourceGroup --name myAKSCluster --output table

And initiate an upgrade with:

az aks upgrade \
    --resource-group myResourceGroup \
    --name myAKSCluster \
    --kubernetes-version 1.27.7

Securing Your Cluster

Security is paramount in any cloud environment. AKS offers various features to secure your cluster and the workloads running on it.

Network Policies: Control traffic flow between pods.
RBAC (Role-Based Access Control): Manage user permissions within the cluster.
Secrets Management: Securely store and manage sensitive information like passwords and API keys.
Azure Active Directory Integration: Integrate AKS authentication with Azure AD for centralized identity management.

Tip: Regularly review your cluster's security configurations and apply the principle of least privilege.

Advanced Management Techniques

Node Pool Management

AKS allows you to create and manage multiple node pools within a single cluster. This is useful for segregating workloads with different hardware requirements or cost considerations.

Key operations include:

Adding new node pools
Deleting node pools
Configuring virtual machine sizes and operating systems for each node pool

Note: The AKS control plane is always managed by Azure and is not part of your node pools.

Backup and Disaster Recovery

Implement robust backup and disaster recovery strategies for your AKS workloads. Consider solutions like Azure Backup for persistent volumes and Velero for backing up Kubernetes resources.

Cost Management

Optimize your AKS costs by right-sizing your node pools, utilizing autoscaling effectively, and choosing appropriate VM sizes. Azure Cost Management + Billing provides tools to monitor and control spending.

Troubleshooting Common Issues

When issues arise, start by examining pod logs, node status, and cluster events. Azure Monitor and Kubernetes command-line tools like kubectl are your primary tools for diagnosis.

# Get pod status
kubectl get pods --all-namespaces

# Describe a specific pod for more details
kubectl describe pod  -n 

# View pod logs
kubectl logs  -n

Warning: Always ensure you have proper RBAC permissions before attempting to troubleshoot or modify cluster resources.

For more in-depth troubleshooting, refer to the dedicated AKS troubleshooting guide.