Deploying MongoDB ReplicaSet with Docker (Public VPS IP and User Authentication Required)

Võ Tấn Đạt — Wed, 16 Apr 2025 03:39:01 +0000

Introduction

Deploying a MongoDB ReplicaSet with Docker efficiently builds a robust database system, ensuring high availability and fault tolerance. I'd like to share the detailed steps based on my real-world experience below.

So the other day, I was working on a project using NestJS + Prisma + MongoDB, and it turned out that Prisma requires a ReplicaSet to work properly.

Deployment Steps

Create Directory Structure

Prepare the necessary directories for data and configuration:

mkdir -p mongodb-replicaset/data/{primary,secondary1,secondary2}
cd mongodb-replicaset

Create a Keyfile for Authentication

The keyfile ensures secure communication between nodes.

mkdir -p mongodb-replicaset/keyfile
openssl rand -base64 756 > keyfile/mongodb-keyfile
chmod 400 keyfile/mongodb-keyfile
sudo chown 999:999 keyfile/mongodb-keyfile

Create a Docker Compose File

Use the following Docker Compose configuration to initialize the ReplicaSet:

version: '3.8'

services:
  mongo-primary:
    image: mongo:latest
    container_name: mongo-primary
    command: mongod --bind_ip_all --replSet rs0 --port 27017 --auth --keyFile /data/keyfile/mongodb-keyfile
    ports:
      - "27017:27017"
    volumes:
      - ./data/primary:/data/db
      - ./keyfile:/data/keyfile
    networks:
      - mongo-network
    restart: always

  mongo-secondary-1:
    image: mongo:latest
    container_name: mongo-secondary-1
    command: mongod --bind_ip_all --replSet rs0 --port 27017 --auth --keyFile /data/keyfile/mongodb-keyfile
    ports:
      - "27018:27017"
    volumes:
      - ./data/secondary1:/data/db
      - ./keyfile:/data/keyfile
    networks:
      - mongo-network
    restart: always
    depends_on:
      - mongo-primary

  mongo-secondary-2:
    image: mongo:latest
    container_name: mongo-secondary-2
    command: mongod --bind_ip_all --replSet rs0 --port 27017 --auth --keyFile /data/keyfile/mongodb-keyfile
    ports:
      - "27019:27017"
    volumes:
      - ./data/secondary2:/data/db
      - ./keyfile:/data/keyfile
    networks:
      - mongo-network
    restart: always
    depends_on:
      - mongo-primary

networks:
  mongo-network:
    driver: bridge

Start Docker Compose
```
docker-compose up -d
```

Configure the ReplicaSet

Connect to the primary node and initialize the ReplicaSet:

docker exec -it mongo-primary mongosh
rs.initiate({
  _id: "rs0",
  members: [
    { _id: 0, host: "mongo-primary:27017", priority: 2 },
    { _id: 1, host: "mongo-secondary-1:27017", priority: 1 },
    { _id: 2, host: "mongo-secondary-2:27017", priority: 1 }
  ]
});

Create an Admin User

use admin;
db.createUser({
  user: "adminUser",
  pwd: "securePassword",
  roles: [ { role: "root", db: "admin" } ]
});

MongoDB Connection String with Authentication (ReplicaSet + Public IP)

In local

mongodb://appUser:appPassword@mongo-primary:27017,mongo-secondary-1:27017,mongo-secondary-2:27017/myApp?replicaSet=rs0&authSource=myApp

For public IP

mongodb://appUser:appPassword@your_vps_ip:27017,your_vps_ip:27018,your_vps_ip:27019/myApp?replicaSet=rs0&authSource=myApp

Conclusion

With the above steps, you can easily and effectively deploy a MongoDB ReplicaSet with Docker. Don't forget to verify your connection and consider any additional security configurations as needed.

Forem: Võ Tấn Đạt

Deploying MongoDB ReplicaSet with Docker (Public VPS IP and User Authentication Required)

Introduction

Deployment Steps

Conclusion