Bare-metal Kubernetes trade-offs

A general look at the trade-off. In my own work this was a move from Azure AKS to bare-metal Hetzner running K3s, described in the case study.

What you can gain

• Control over the runtime and the node. Some workloads, nested containers among them, need settings a managed service may not expose.
• Predictable cost. Fixed-price servers can be cheaper than the equivalent metered cloud services for steady workloads.
• Fewer layers. Fewer abstractions between the workload and the hardware can mean lower latency.

What you take on

• The control plane. Upgrades, certificates and etcd health become your job.
• Hardware failure. Nobody replaces a failed node for you. Spare capacity and fast rescheduling matter.
• The surrounding services. Load balancing, storage and backups that a cloud provides by default need an answer.

A reasonable test

Choose bare metal when a specific constraint justifies the operational work, and be explicit about which constraint it is. K3s helps by keeping the footprint small, which suits a small team.