DevOps Lab

Personal DevOps homelab used to practice Docker, Linux, networking, storage and backup strategies.

This repository does NOT contain real production data. It represents a cleaned and documented reference architecture based on a real home server.

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Goals

• Practice Docker and docker-compose
• Prepare foundation for Kubernetes (containerization, networking, storage concepts)
• Design persistent storage for containers
• Separate infrastructure from application data
• Implement and automate backups
• Document operational decisions (runbooks)
• Prepare for Junior DevOps / SRE interviews

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Environment

Host system:

• Debian Linux
• Single-node homelab (laptop used as server)

Main components:

• Docker
• docker-compose
• Bash scripts
• rsync backups
• Reverse proxy (nginx)

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Monitoring

                          ┌─────────────────────────┐
                          │          Nginx          │
                          │      Reverse Proxy      │
                          └─────────────┬───────────┘
                                        │
                                        ▼
                                ┌───────────────┐
                                │    Grafana    │
                                │   Dashboards  │
                                └───────┬───────┘
                                        │
                     ┌──────────────────┴──────────────────┐
                     │                                     │
                     ▼                                     ▼
              ┌───────────────┐                     ┌──────────────┐
              │  Prometheus   │                     │     Loki     │
              │ Metrics Store │                     │  Log Storage │
              └───────┬───────┘                     └──────┬───────┘
                      │                                     │
          ┌───────────┴───────────┐                         │
          │                       │                         │
          ▼                       ▼                         ▼
   ┌──────────────┐       ┌───────────────┐         ┌───────────────┐
   │   cAdvisor   │       │ Node Exporter │         │    Promtail   │
   │Container Stats│      │ Host Metrics  │         │  Log Collector│
   └──────────────┘       └───────────────┘         └───────────────┘
                                                        │
                                                        ▼
                                               Docker container logs

The monitoring stack combines metrics and log collection.

Metrics pipeline:

• Node Exporter exposes host system metrics
• cAdvisor exposes container resource metrics
• Prometheus scrapes metrics from both services
• Grafana queries Prometheus to visualize metrics

Logging pipeline:

• Promtail collects logs from Docker containers
• Loki stores and indexes log data
• Grafana queries Loki to visualize logs

Only Grafana is exposed externally through the reverse proxy. All other services communicate internally through the Docker network.

The monitoring example:

Monitoring Setup Guide

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Infrastructure Dashboard

A lightweight dashboard is deployed using Homepage to provide a central entry point for internal services.

The dashboard aggregates links to commonly used infrastructure components such as:

• monitoring (Grafana)
• service interfaces
• development tools
• internal applications

This allows quick navigation across the self-hosted environment without exposing multiple ports or remembering individual service URLs.

Example deployment configuration is available in:

docker_compose_services/homepage/

Example configuration: docker_compose_services/homepage

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Repository Structure

docker_services/
Contains docker-compose files for each service. Only infrastructure definitions, no data.

app_data/
Example structure for persistent application data. Used only as reference, not real data.

ops/
Operational documentation and scripts.

architecture/
High-level explanations of system design decisions.

examples/
Sanitized examples of logs, configs and outputs.

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Services Overview

Services included in this lab:

• nginx (reverse proxy)
• monitoring (glances)
• media services (example)
• application containers (example)

Each service:

• runs in Docker
• uses bind-mounted persistent data
• is isolated in a custom Docker network

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Storage Model

Principles:

• Containers are stateless
• All persistent data lives outside containers
• Application data and infrastructure are separated

High-level layout:

• docker_services → how services are started
• app_data → what services store
• backup → offline backup / Cloud

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Backups

Backup strategy:

• Tool: rsync
• Target: offline USB drive
• Mode: incremental with deletion

Backups include:

• application data
• service configuration
• infrastructure definitions

Backups exclude:

• operating system
• temporary files
• caches

See: ops/runbooks/backup.md

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Operations

This repository contains runbooks for:

• backups
• restore procedures
• permission issues
• common container failures

The goal is to document operational thinking, not just configuration.

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Security Notes

• No real credentials are stored
• All secrets are replaced with placeholders
• .env files are provided as examples only

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Status

This lab is actively evolving. Structure and documentation improve over time as new topics are learned. Kubernetes is planned as a next step after stabilizing the Docker-based setup.

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Disclaimer

This is a learning and practice project. It is not intended to be used as a production-ready setup without adaptation.