Minecraft Kubernetes Helm Chart Guide

Overview

This document explains all the Helm chart components used to deploy a Minecraft Java Edition server on Kubernetes with host-mounted storage and RCON support.

Chart Structure

    minecraft-server/
    ├─ chart.yaml
    ├─ values.yaml
    └─ templates/
        ├─ deployment.yaml
        ├─ service.yaml
        ├─ pv.yaml
        └─ pvc.yaml

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Chart.yaml

chart.yaml

This defines metadata about the Helm chart:

apiVersion: v2
name: minecraft-server
version: 0.1.0
description: Minecraft Java Server on Kubernetes

values.yaml

values.yaml

This file contains all configurable values used in the chart.

For now the rcon binds to .10 and not .190 idk why yet.

Important fields:

image:
  repository: eclipse-temurin
  tag: latest
  pullPolicy: IfNotPresent

minecraft:
  memoryMax: 15G
  memoryMin: 8G
  jarFile: server.jar
  rconPassword: "SuperSecret123"

service:
  type: NodePort
  port: 25565
  nodePort: 32565
  bindIP: 192.168.2.10
  rconBindIP: 192.168.2.190
  rconPort: 25575

persistence:
  hostPath: /mnt/DATA/minecraft

deployment.yaml

Deployment Explanation

The Deployment runs the Minecraft server and mounts your host directory:

deployment.yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  name: minecraft-server
spec:
  replicas: 1
  selector:
    matchLabels:
      app: minecraft-server
  template:
    metadata:
      labels:
        app: minecraft-server
    spec:
      hostNetwork: true
      dnsPolicy: ClusterFirstWithHostNet
      containers:
        - name: minecraft
          image: {{ .Values.image.repository }}:{{ .Values.image.tag }}
          imagePullPolicy: {{ .Values.image.pullPolicy }}
          workingDir: /data
          command: ["java"]
          args: ["-Xmx{{ .Values.minecraft.memoryMax }}", "-Xms{{ .Values.minecraft.memoryMin }}",
                 "-jar", "{{ .Values.minecraft.jarFile }}", "nogui"]
          volumeMounts:
            - name: minecraft-data
              mountPath: /data
      volumes:
        - name: minecraft-data
          hostPath:
            path: {{ .Values.persistence.hostPath }}

Purpose:

• hostNetwork: true binds Minecraft directly to host IPs.
• /mnt/DATA/minecraft on the host is mapped to /data in the container.
• Minecraft server reads and writes files directly in the host directory.
• server.jar must exist in /mnt/DATA/minecraft.

service.yaml

Service Explanation

service.yaml

apiVersion: v1
kind: Service
metadata:
  name: minecraft-service
spec:
  type: {{ .Values.service.type }}
  selector:
    app: minecraft-server
  ports:
    - port: {{ .Values.service.port }}
      targetPort: {{ .Values.service.port }}
      nodePort: {{ .Values.service.nodePort }}

Purpose:

• Exposes Minecraft to the network via NodePort.
• Since hostNetwork: true, the server also binds directly to the host IP.

pv.yaml

Storage Configuration

pv.yaml

apiVersion: v1
kind: PersistentVolume
metadata:
  name: minecraft-pv
spec:
  capacity:
    storage: 100Gi
  accessModes:
    - ReadWriteOnce
  hostPath:
    path: {{ .Values.persistence.hostPath }}

pvc.yaml

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: minecraft-pvc
spec:
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 100Gi

---

How to Deploy

1. Prepare Host Directory

sudo mkdir -p /mnt/DATA/minecraft
sudo chmod -R 777 /mnt/DATA/minecraft

2. Add your Minecraft server JAR

Place your server.jar into:

/mnt/DATA/minecraft/server.jar

3. Install the Helm Chart

helm install mc ./minecraft-server -n minecraft --create-namespace

4. Check Deployment

kubectl get pods -n minecraft
kubectl logs -f deployment/minecraft-server -n minecraft

5. Edit server.properties

Example:

    enable-rcon=true
    rcon.port=25575
    rcon.password=SuperSecret123
    rcon.ip=192.168.2.190
    server-ip=192.168.2.10
    server-port=25565

Save it to:

/mnt/DATA/minecraft/server.properties

6. Connect to the Server

Use:

192.168.2.10:25565

7. RCON Access

192.168.2.190:25575 password: SuperSecret123

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