Kubermatic KubeLB

What is KubeLB?

KubeLB is a Kubernetes-native, multi-tenant load-balancing platform by Kubermatic. It centralizes Layer 4 and Layer 7 traffic management for fleets of Kubernetes clusters across cloud, on-premises, and bare-metal environments.

A management cluster runs the load-balancing data plane, while KubeLB Cloud Controller Manager (CCM) agents connect tenant clusters and propagate their requested configuration. Workloads continue to use Kubernetes APIs: Services of type LoadBalancer for Layer 4, and Ingress or Gateway API resources for Layer 7.

Start Here

• Understand the architecture and how the management and tenant clusters interact.
• Check compatibility and compare Community and Enterprise features before choosing a deployment.
• Install KubeLB, starting with the management cluster and then connecting tenant clusters.
• Expose workloads with a Layer 4 LoadBalancer Service, Ingress, or the Gateway API.
• Migrate from Ingress to the Gateway API with KubeLB automation, the CLI, or the dashboard.
• Operate KubeLB with the dashboard, review security guidance, and check the release notes.

Motivation and Background

Kubernetes does not offer any implementation for load balancers and in turn relies on the in-tree or out-of-tree cloud provider implementations to take care of provisioning and managing load balancers. This means that if you are not running on a supported cloud provider, your services of type LoadBalancer will never be allotted a load balancer IP address. This is an obstacle for bare-metal Kubernetes environments.

There are solutions available like MetalLB, Cilium, etc. that solve this issue. However, these solutions are focused on a single cluster where you have to deploy the application in the same cluster where you want the load balancers. This is not ideal for multi-cluster environments since you have to configure load balancing for each cluster separately, which makes IP address management not trivial.

Application load balancing has the same constraint: an external application like ingress-nginx or Envoy Gateway needs to be deployed in the cluster, and securing traffic requires further tools to manage DNS, TLS certificates, and web application firewalls.

KubeLB solves this problem with a centralized management cluster that runs the data plane for multiple Kubernetes clusters across multi-cloud and on-premise environments. Load balancing for a whole fleet of clusters is configured and enforced in one place, with a consistent experience for developers. Air-gapped environments without internet access are supported in the Enterprise Edition; see the Air-Gap Installation guide.

Table of Contents

• Architecture
• Community vs Enterprise Edition
• Compatibility Matrix
• Installation
• Guides
• Ingress to Gateway API Migration
• KubeLB Dashboard
• KubeLB CLI
• Observability
• Insights
• Supply Chain Security
• Support Policy
• References
• Release Notes

Further Reading

• Introducing KubeLB
• KubeLB Whitepaper
• KubeLB - GitHub Repository

Visit kubermatic.com for further information.