Overview

This case study documents the design and deployment of a production-grade Kubernetes cluster built on bare-metal dedicated servers from an affordable cloud provider. The solution delivers a complete DevSecOps pipeline. It includes distributed storage, centralized logging, and automated CI/CD workflows. The team achieved full infrastructure control while maintaining strict cost efficiency.

Key Outcomes

Self-managed Kubernetes cluster on bare-metal servers
70 to 80% cost savings compared to managed Kubernetes services
Complete ownership of infrastructure and security
Enterprise-ready observability with centralized logging
Automated CI/CD process supported by a monorepo architecture

Key Challenges

Organizations face a critical decision when deploying Kubernetes: managed services versus self-managed clusters. While managed services offer convenience, they come with:

High monthly costs with managed services such as EKS, GKE, and AKS
Limited customization options in managed Kubernetes environments
Vendor lock-in concerns due to platform dependencies
Reduced control over infrastructure-level security configurations
Additional network egress charges
Premium pricing required for enterprise-grade features

Solution: Bare-Metal Kubernetes Platform

The team selected bare-metal servers from a cost-effective cloud provider. Multiple industry benchmarks supported this decision.

Cost Optimization

Predictable monthly billing with dedicated hardware
No managed service markups or egress charges

Performance

Direct hardware access with zero virtualization overhead
Network latency is three times lower on bare-metal compared to VMs
Container performance improves by 25 to 30% on bare-metal
VMs retain 99% of bare-metal performance, yet the remaining 1% matters at scale

Control

Full control across the stack
Single-tenant architecture improves security
Custom kernel and hardware tuning
No vendor lock-in or platform restrictions

Security

Isolated private network with custom policies
Enhanced compliance support
Full control over all security configurations
Reduced attack surface with dedicated infrastructure

Flexibility

Customization at every layer
Tailored configurations for diverse workloads
Strong support for ML and analytics-heavy applications

Business Objectives

Build a production-ready Kubernetes environment
Control operational costs
Ensure high availability and data persistence
Establish strong observability
Automate deployments through CI/CD
Meet security and compliance standards

Technical Architecture

Infrastructure Foundation

Hosting Platform

Provider: Affordable cloud provider
Server Type: Bare-metal dedicated servers
OS: Ubuntu 24.04 LTS
Kubernetes Distribution: Kubeadm (self managed)

Network Architecture

Private network through vRack
Isolated public and private interfaces
Secure internal communication

Infrastructure Components

Kubernetes Control Plane (Kubeadm)

Purpose: Orchestration and management of containerized workloads

Components:

kube-apiserver: REST API for cluster operations
kube-scheduler: Pod placement decisions
kube-controller-manager: Maintains desired state
etcd: Distributed key-value store for cluster data

Why Kubeadm:

Industry-standard installation method
Full control over cluster configuration
Easy upgrades and maintenance
Active community support
Production-ready certification

Configuration Highlights:

Custom pod network CIDR for vRack integration
Configured for high availability
Integrated with private network for secure communication
Certificate management with automatic rotation

Storage Layer - Longhorn

Purpose: Cloud-native distributed block storage for Kubernetes

Architecture:

Distributed storage across all worker nodes
Replication factor configurable per volume
Thin provisioning with over-commit support
Incremental snapshots and backups

Key Features:

Container Storage Interface (CSI): Native Kubernetes integration
Replication: Data redundancy across multiple nodes
Snapshots: Point-in-time volume snapshots
Backups: Secondary backup to S3-compatible storage
Web UI: Centralized management dashboard

Benefits:

No dependency on cloud provider storage
Cost-effective compared to cloud block storage
High performance with local storage
Built-in disaster recovery features

Longhorn Storage Replication:

CI/CD Pipeline - Jenkins with Monorepo

Architecture: Single repository containing all application components

Monorepo Benefits:

Single source of truth for all code
Atomic commits across multiple services
Simplified dependency management
Consistent versioning
Easier refactoring across services

Integration Points:

Git webhooks trigger builds automatically
Docker registry for image storage
Kubernetes API for deployments
Slack/email notifications for pipeline status

CI/CD Pipeline Flow:

Logging Stack - Loki + Promtail + Grafana

Architecture: Modern log aggregation inspired by Prometheus

Promtail

Deployment: DaemonSet (runs on every node)

Responsibilities:

Discovers log files from containers
Attaches metadata labels
Parses and processes log lines
Streams logs to Loki

Loki

Deployment: StatefulSet with Longhorn PVC

Architecture:

Index-free log aggregation
Label-based organization (like Prometheus)
Object storage for log chunks
Efficient compression

Storage Requirements:

Persistent volume for index and chunks
Longhorn provides replication
Configurable retention policies

Grafana

Purpose: Visualization and dashboard platform

Features:

Loki data source integration
LogQL query language
Pre-built dashboard templates
Alert management
User access control

Dashboard Examples:

Application error logs
Request/response logs by service
Container restart events
Resource usage correlation

Benefits:

Cost-effective (no per-GB indexing cost)
Easy to operate and scale
Powerful query language
Integrated with existing Grafana dashboards
Low resource overhead

Logging Flow Architecture:

Cost Analysis

Bare-Metal Cost Breakdown

Three dedicated servers: ~$300 per month
vRack: No cost
Bandwidth: No cost for 1Gbps with 5TB included
Total monthly cost: ~$300/month
Annual cost: $3,600-4,000

Advantages

No egress bandwidth charges
No load balancer fees
No managed service premiums
Predictable spending
Higher performance per dollar

Trade-offs

Additional operational work
Manual updates and maintenance
Need for internal expertise
No automatic scaling for the control plane

Bare-metal is effective when:

Teams understand Kubernetes operations
Cluster is relatively stable
Workloads scale predictably
The organization values infrastructure control

Not recommended for:

Small team without K8s experience
Rapid scaling requirements
Limited operational resources
Prefer managed services
Need 24/7 support SLA

Conclusion

The SaaS company successfully transformed its cloud deployment process. This helped them build a fully automated software delivery ecosystem. They brought together infrastructure automation, continuous deployment, and security monitoring. This completely changed the way their platform operates in the cloud.

The combination of Terraform for infrastructure management and GitHub Actions for CI/CD automation delivered measurable business value. Teams can now deploy with confidence multiple times per day, maintain complete security compliance, and respond to customer needs faster than ever before.

Key Success Factors

Strong Kubernetes expertise
Clear architectural planning
Reliable tools such as Longhorn, Loki, and Jenkins
Early automation for deployments
Deep observability from day one

Appendix

Technology Stack Summary

Component	Technology	Purpose
Infrastructure	Affordable Cloud Provider	Dedicated servers
OS	Ubuntu 24.04 LTS	Operating system
Network	vRack	Private networking
Orchestration	Kubernetes (Kubeadm)	Container orchestration
Storage	Longhorn	Distributed block storage
CI/CD	Jenkins	Automation pipeline
Repository	Self Hosted Gitlab	Source code management
Log Collection	Promtail	Log agent
Log Storage	Loki	Log aggregation
Visualization	Grafana	Dashboards

Key Metrics

Cluster Size: 3+ nodes
Storage Replication: 3x
Log Retention: 30 days
Deployment Frequency: Multiple per day
Cost Savings: 50-70% vs managed K8s
Setup Time: 5-6 weeks

Bare-Metal Kubernetes Infrastructure: A DevSecOps Case Study