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Source: oceanid/docs/adr/0001-k3s-cluster-architecture.md | ✏️ Edit on GitHub

ADR-0001: K3s Cluster Architecture

Date: 2025-09-01 Status: Accepted Author: Infrastructure Team

Context

We need a lightweight Kubernetes distribution that can run on bare metal servers while providing production-grade features.

Decision

We will use K3s as our Kubernetes distribution with:

  • 3-node cluster (1 control plane, 2 workers)
  • Flux CD for GitOps deployment
  • Cloudflare Tunnel for secure ingress
  • Pulumi for infrastructure as code

Consequences

Positive

  • Lightweight and resource-efficient
  • Built-in etcd for high availability
  • Easy to manage and upgrade
  • Native support for ARM64 (GPU nodes)

Negative

  • Some enterprise features require additional configuration
  • Smaller ecosystem compared to full Kubernetes
  • Limited to single-region deployment

References