Virtual Clusters

VCluster (Virtual Cluster) enables you to run multiple isolated Kubernetes clusters (vclusters) within a single host cluster. This is ideal for multi-tenant, development, testing, and regional deployments on AKS, EKS, GKE, or on-prem clusters.

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Real-Life Use Cases

• Multi-Tenant SaaS: Isolate customer workloads in separate vclusters for security and compliance.

• Dev/Test Environments: Spin up ephemeral vclusters for feature branches, CI/CD, or integration testing without impacting production.

• Regional Deployments: Deploy vclusters per region to meet data residency or regulatory requirements.

• Platform Engineering: Empower teams to manage their own vclusters with full Kubernetes API access, while centralizing infrastructure management.

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Step-by-Step: Deploying a vcluster

1. Install vcluster CLI:

   curl -sSL https://vcluster.com/download | bash
   # or use Homebrew
   brew install vcluster

2. Create a vcluster in a namespace:

   kubectl create namespace dev-team
   vcluster create dev-vcluster -n dev-team

3. Connect to the vcluster:

   vcluster connect dev-vcluster -n dev-team
   # This updates your kubeconfig to point to the vcluster
   kubectl get nodes

4. Deploy workloads in the vcluster:

   kubectl apply -f my-app.yaml

5. List and manage vclusters:

   vcluster list
   vcluster delete dev-vcluster -n dev-team

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Best Practices

• Use separate namespaces for each vcluster to ensure isolation.

• Automate vcluster lifecycle (creation, deletion) in CI/CD pipelines for ephemeral environments.

• Monitor resource usage in the host cluster to avoid noisy neighbor issues.

• Use RBAC and network policies to restrict access between vclusters.

• Store vcluster configuration and manifests in Git for GitOps workflows.

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Common Pitfalls

• Overcommitting host cluster resources (CPU, memory) can impact all vclusters.

• Not cleaning up unused vclusters leads to resource waste.

• Assuming vcluster isolation is equivalent to physical cluster isolation (some host-level risks remain).

• Manual changes outside of Git in GitOps-managed environments.

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References

• vcluster Official Docs
• vcluster GitHub
• Multi-Tenancy Patterns