Collection of Docker Compose Configuration

Set Static IP Addresses for Services using IPAM

In Docker Compose, you can assign static IP addresses to your containers within a custom network. This ensures consistent communication between services, especially when specific IP addresses are required. Docker Compose Network

💡 Tip: Use a unique subnet (e.g., 172.99.0.0/24) to avoid conflicts with existing networks. Verify active Docker networks by running:

docker network ls

Example with Static IPs

version: '3.9'

services:
  app:
    image: your-app-image
    container_name: app_service
    ...
    networks:
      example_network:
        ipv4_address: 172.99.0.10

  db:
    image: your-db-image
    container_name: db_service
    ...
    networks:
      example_network:
        ipv4_address: 172.99.0.2

  nginx:
    image: nginx:latest
    container_name: nginx_service
    ...
    networks:
      example_network:
        ipv4_address: 172.99.0.3

networks:
  example_network:
    driver: bridge
    ipam:
      config:
        - subnet: 172.99.0.0/24
    external: false

Inspect the created network to verify assignments:

docker network inspect example_network

Set Multiple Subnets

Defining multiple subnets in a single Docker network allows you to:

1. Separate groups of services (e.g., databases in one subnet, caches in another).

2. Use different routing or gateways for different traffic flows.

3. Allocate different IP address spaces for legacy services vs dynamic ones.

version: '3.9'

services:
  app:
    image: your-app
    networks:
      example_network:
        ipv4_address: 172.99.0.10

  cache:
    image: redis:7
    networks:
      example_network:
        ipv4_address: 172.99.1.5

networks:
  example_network:
    driver: bridge
    ipam:
      config:
        - subnet: 172.99.0.0/24
        - subnet: 172.99.1.0/24

Set IP Range

What it is / When to use?

The ip_range option restricts the pool of IP addresses Docker can dynamically assign within a subnet. This is useful when:

1. You want to reserve a portion of the subnet for static IP assignments.

2. You need stricter control over which addresses Docker is allowed to allocate.

3. You’re mixing static and dynamic IPs in the same subnet.

version: '3.9'

services:
  app1:
    image: your-app
    networks:
      example_network: {}

  app2:
    image: your-app
    networks:
      example_network: {}

  db:
    image: postgres:16
    networks:
      example_network:
        ipv4_address: 172.99.0.5   # static, outside the dynamic range

networks:
  example_network:
    driver: bridge
    ipam:
      config:
        - subnet: 172.99.0.0/24
          ip_range: 172.99.0.128/25

Add Healthcheck to Service

Ensure containers are only marked as healthy when their core functionality is available and responsive.

APP/Web Server

services:
...
  api:
    container_name: api
    restart: unless-stopped
    ports:
      - "8000:8000"
    healthcheck:
      test: ["CMD", "curl", "--fail", "http://localhost:8000/health"]
      interval: 30s
      timeout: 10s
      retries: 3
      start_period: 5s
...

MySQL/MariaDB

services:
...
  mysql:
    image: mysql:8.0
    container_name: mysql
    restart: unless-stopped
    environment:
      MYSQL_ROOT_PASSWORD: rootpass
      MYSQL_DATABASE: db
      MYSQL_USER: user
      MYSQL_PASSWORD: pass
    ports:
      - "3306:3306"
    healthcheck:
      test: ["CMD", "mysqladmin", "ping", "-h", "localhost", "-uroot", "-prootpass"]
      interval: 30s
      timeout: 10s
      retries: 5
      start_period: 20s
...

PostgreSQL

services:
...
  postgres:
    image: postgres:16
    container_name: postgres
    restart: unless-stopped
    environment:
      POSTGRES_USER: user
      POSTGRES_PASSWORD: pass
      POSTGRES_DB: db
    ports:
      - "5432:5432"
    healthcheck:
      test: ["CMD-SHELL", "pg_isready -U user -d db -h localhost"]
      interval: 30s
      timeout: 10s
      retries: 5
      start_period: 20s
...

Redis

services:
...
  redis:
    image: redis:7
    container_name: redis
    restart: unless-stopped
    ports:
      - "6379:6379"
    healthcheck:
      test: ["CMD", "redis-cli", "ping"]
      interval: 30s
      timeout: 10s
      retries: 5
      start_period: 10s
...

💡 Tips:

• Use a lightweight endpoint (e.g., /health) instead of hitting the main routes.
• Configure intervals and timeouts (too frequent checks may overload the service).
• Add a start period for services that need warm-up time before they are ready.
• Ensure the healthcheck matches real readiness, not just process existence.
• Combine with depends_on: condition: service_healthy in Docker Compose to control startup order.