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Running databases in Docker is a fast way to spin up development environments and is increasingly common in production when combined with proper volumes, backups, and resource limits. This guide covers all three of the most common database engines.

Prerequisites

• Docker Engine and Docker Compose installed
• Root or sudo access

MySQL

services:
  mysql:
    image: mysql:8.0
    container_name: mysql
    restart: unless-stopped
    environment:
      MYSQL_ROOT_PASSWORD: ${MYSQL_ROOT_PASSWORD}
      MYSQL_DATABASE: ${MYSQL_DATABASE}
    ports:
      - "3306:3306"
    volumes:
      - mysql_data:/var/lib/mysql

volumes:
  mysql_data:

Connect from the host:

docker exec -it mysql mysql -u root -p

PostgreSQL

services:
  postgres:
    image: postgres:16
    container_name: postgres
    restart: unless-stopped
    environment:
      POSTGRES_PASSWORD: ${POSTGRES_PASSWORD}
      POSTGRES_DB: ${POSTGRES_DB}
    ports:
      - "5432:5432"
    volumes:
      - postgres_data:/var/lib/postgresql/data

volumes:
  postgres_data:

Connect from the host:

docker exec -it postgres psql -U postgres

Redis

services:
  redis:
    image: redis:7
    container_name: redis
    restart: unless-stopped
    command: redis-server --requirepass ${REDIS_PASSWORD}
    ports:
      - "6379:6379"
    volumes:
      - redis_data:/data

volumes:
  redis_data:

Connect from the host:

docker exec -it redis redis-cli -a YOUR_REDIS_PASSWORD

Should You Publish Database Ports Publicly?

Generally, no. If only other containers in the same Compose project need access, omit the ports: section entirely — they can still reach the database by service name over the internal Compose network. Only publish a port if you specifically need external access, and restrict it at the firewall level.

Backing Up Each Database

MySQL:

docker exec mysql mysqldump -u root -p"$MYSQL_ROOT_PASSWORD" --all-databases > backup.sql

PostgreSQL:

docker exec postgres pg_dumpall -U postgres > backup.sql

Redis (triggers an RDB snapshot):

docker exec redis redis-cli -a YOUR_PASSWORD SAVE

Restoring MySQL

cat backup.sql | docker exec -i mysql mysql -u root -p"$MYSQL_ROOT_PASSWORD"

Common Errors

Data lost after docker compose down — confirm a named volume is configured; without one, data lives only in the container's writable layer and is lost on removal.

"Connection refused" from another container — verify both services are on the same Compose project/network, and connect using the service name (e.g. mysql), not localhost.

Best Practices

• Always use named volumes for database data
• Set strong passwords via a .env file, never hardcoded
• Avoid publishing database ports publicly unless absolutely necessary
• Schedule regular automated dumps as part of your backup routine

FAQ

Is running a production database in Docker a good idea?
It's widely done successfully, provided you use persistent volumes, resource limits, regular backups, and don't expose the database port to the public internet.

Related Articles

• Docker Volumes: Persisting Data
• Docker Compose .env Files and Environment Variables Explained
• How to Set Up Automated VPS Backups