Kubernetes in the Cloud vs. Bare Metal: A Comparative Study of Network Costs
Rodrigo Mompo Redoli, Amjad Ullah
TL;DR
This study quantifies network-cost differences for Kubernetes workloads on bare-metal versus managed cloud environments within a FinOps framework. Using a controlled benchmarking setup with Plex-based video traffic, they deploy identical clusters (bare-metal via K3d and cloud via EKS), perform load testing with K6, and leverage Kubecost to attribute network costs by traffic type (in-zone, in-region, internet). The results show substantial network-cost savings for bare metal in the tested scenario, with cloud deployment incurring about 850% higher costs at peak usage, though the authors caution that traffic patterns and ingress costs can shift this balance. The work provides a practical methodology and data-driven basis for cost-driven hosting decisions in cloud-native environments and highlights the need for holistic FinOps practices when evaluating network expenditures.
Abstract
Modern cloud-native applications increasingly utilise managed cloud services and containerisation technologies, such as Kubernetes, to achieve rapid time-to-market and scalable deployments. Organisations must consider various factors, including cost implications when deciding on a hosting platform for containerised applications as the usage grows. An emerging discipline called FinOps combines financial management and cloud operations to optimise costs in cloud-based applications. While prior research has explored system-level optimisation strategies for cost and resource efficiency in containerized systems, analysing network costs in Kubernetes clusters remains underexplored. This paper investigates the network usage and cost implications of containerised applications running on Kubernetes clusters. Using a methodology that combines measurement analysis, experimentation, and cost modelling, we aim to provide organisations with actionable insights into network cost optimisation. Our findings highlight key considerations for analysing network expenditures and evaluating the potential cost benefits of deploying applications on cloud providers. Overall, this paper contributes to the emerging FinOps discipline by addressing the financial and operational aspects of managing network costs in cloud-native environments.