MongoDB replicaset on Docker

connect.md

Setup allow to connect mongo replicaset running inside docker from host machine.

Start

Production: docker compose up -d

Development: docker compose -f docker-compose.yml -f docker-compose.dev.yml up -d

run init_replica.sh to setup mongodb replica after container start

Connect using Mongo Compass or Navicat

Addresses

• mongodb_1:27017
• mongodb_2:27017
• mongodb_3:27017

ReplicaSet: -rs0

Connection String

mongodb://mongodb_1:27017,mongodb_2:27017,mongodb_3:27017?replicaSet=rs0

Restore database

docker exec -i mongodb_1 mongorestore --archive --gzip < ~/Downloads/backup.gz

docker-compose.override.yml

version: '3.8'
services:
  mongodb_1:
    ports:
      - 27001:27017
  mongodb_2:
    ports:
      - 27002:27017
  mongodb_3:
    ports:
      - 27003:27017

docker-compse.dev.yml

version: '3.8'
services:
  mongodb_1:
    restart: "no"
    ports:
      - 127.0.10.1:27017:27017
  mongodb_2:
    restart: "no"
    ports:
      - 127.0.10.2:27017:27017
  mongodb_3:
    restart: "no"
    ports:
      - 127.0.10.3:27017:27017

docker-compse.yml

version: '3.8'
services:
  mongodb_1:
    container_name: mongodb_1
    image: "mongo:latest"
    networks: 
      - mongo_backend
    entrypoint: [ "/usr/bin/mongod", "--bind_ip_all", "--replSet", "rs0" ]
    restart: always
  mongodb_2:
    container_name: mongodb_2
    image: "mongo:latest"
    networks: 
      - mongo_backend
    entrypoint: [ "/usr/bin/mongod", "--bind_ip_all", "--replSet", "rs0" ]
    restart: always
  mongodb_3:
    container_name: mongodb_3
    image: "mongo:latest"
    networks: 
      - mongo_backend
    entrypoint: [ "/usr/bin/mongod", "--bind_ip_all", "--replSet", "rs0" ]
    restart: always
networks:
  mongo_backend:

hosts

# /etc/hosts
# For development
127.0.10.1  mongodb_1
127.0.10.2  mongodb_2
127.0.10.3  mongodb_3

init_replica.sh

#!/bin/bash
echo Checking replica status
status=$(docker exec -t mongodb_1 mongo --eval "rs.status().code" | tail -n1)
if [[ "$status" == *"94"* ]]; then
	mongoAddr1=mongodb_1
	mongoAddr2=mongodb_2
	mongoAddr3=mongodb_3
	replica="rs.initiate(
	  {
	    _id: 'rs0',
	    members: [
	      { _id: 0, host: '$mongoAddr1:27017' },
	      { _id: 1, host: '$mongoAddr2:27017' },
	      { _id: 2, host: '$mongoAddr3:27017' },
	    ]
	  }
	)"

	echo Creating replica with id: rs0
	docker exec -t mongodb_1 mongo --eval "$replica"
fi