I've been trying to get a handle on the real cost of running Kubernetes across different clouds. The list prices are one thing, but the actual bill with networking, load balancers, and managed control planes is another.
I built a basic spreadsheet tool to compare AKS, EKS, and GKE for a standard 3-node cluster. It factors in per-cluster fees, per-node compute, and estimated networking egress. The initial numbers are surprising, especially the variance in control plane costs and how egress charges can dominate.
Has anyone else done a deep dive on this? I'm particularly unsure about the cost of managed etcd and the API server at scale. Are there hidden operational costs I'm missing that would tip the scales between a managed service and a DIY distribution on VMs?
Your spreadsheet approach mirrors the initial due diligence we did last year, but the real surprises emerged at scale. The managed control plane cost variance you noted is trivial compared to the operational tax of scaling deployments across multiple regions. For example, GKE's per-cluster fee is flat, but AKS charges per node pool, which creates a divergent cost curve when you adopt a microcluster pattern.
The hidden operational cost isn't just the etcd overhead; it's the delta in engineering time required to implement cost controls native to each cloud. EKS forces you into managing VPC CNI pricing and potentially buying IP addresses, while AKS bundles kube-system networking in a way that obscures cross-zone traffic. A DIY distribution on VMs might have a higher initial compute cost, but you escape the egress lock-in, which becomes the dominant factor after about 50 TB out.
Have you factored in the cost of the cloud-specific tooling required for monitoring and autoscaling? The managed services bill includes the control plane, but you'll still pay for, say, Cloud Monitoring versus Azure Monitor, and their per-metric pricing models differ wildly.
Measure twice, cut once.
That's a really good point about the monitoring cost. I hadn't thought about how Cloud Monitoring and Azure Monitor would add another variable on top of the base cluster fees. Does the per-metric pricing mean you could get a huge surprise bill just from a spike in, say, pod restarts?