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Hybrid Setup

Connect multiple Kubernetes clusters across different cloud providers using Cilium Cluster Mesh for seamless cross-cluster workload communication.

Cilium Cluster Mesh​

Cilium Cluster Mesh provides:

  • Cross-cluster service discovery
  • Shared service load balancing
  • Network policy enforcement across clusters
  • Transparent encryption

Use Cases​

Use CaseDescription
Multi-cloud resilienceRun workloads across Hetzner + Azure for redundancy
Geographic distributionPlace clusters close to users in different regions
Cost optimizationUse cheaper providers for burst capacity
Hybrid cloudConnect on-premises with cloud providers
MigrationGradually move workloads between clusters

Example: Hetzner + Azure​

┌─────────────────┐         ┌─────────────────┐
│  Hetzner Cluster │◄──────►│  Azure Cluster  │
│                 │ Cilium  │                 │
│  Control Plane  │ Cluster │  Control Plane  │
│  Worker Nodes   │  Mesh   │  Worker Nodes   │
└─────────────────┘         └─────────────────┘

Prerequisites​

  1. Multiple KubeAid clusters deployed (see Cloud Providers)
  2. Network connectivity between clusters (routable IPs or VPN)
  3. Cilium installed on all clusters (included by default)
  4. Compatible Cilium versions across clusters
  5. Unique cluster names in the mesh

Setup Steps​

  1. Enable Cluster Mesh:
cilium clustermesh enable --context <cluster1-context>
cilium clustermesh enable --context <cluster2-context>
  1. Connect clusters:
cilium clustermesh connect \
  --context <cluster1-context> \
  --destination-context <cluster2-context>
  1. Verify connectivity:
cilium clustermesh status --context <cluster1-context>

For detailed configuration, see the Cilium Cluster Mesh documentation.

Hetzner Hybrid Mode​

Note: This is different from Cilium Cluster Mesh. Hybrid mode creates a single cluster with mixed node types, not a mesh of separate clusters.

Hetzner's built-in hybrid mode runs:

  • Control plane in HCloud (VMs)
  • Worker nodes in HCloud and/or Bare Metal (Hetzner Robot)

Hybrid clusters require two Cloud Controller Manager (CCM) instances - ccm-hcloud for networking and InternalIP assignment on HCloud nodes, and ccm-hetzner for bare-metal node lifecycle with hrobot:// provider IDs. The Hetzner CCM cannot run its route controller and Robot support simultaneously, so they are split. Cilium uses VXLAN tunnel mode so pod networking works without routes programmed in the HCloud network.

See Cloud Providers - Hetzner Hybrid for full architecture details and setup instructions.

See Also​