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Docker Compose Cheat Sheet

Basic Commands

Starting Services

# Start all services in detached mode (background)
docker compose up -d

# Start specific service(s)
docker compose up -d postgres kafka

# Start and view logs (foreground)
docker compose up

# Start and rebuild images
docker compose up -d --build

Stopping Services

# Stop all running services (keeps containers)
docker compose stop

# Stop specific service
docker compose stop postgres

# Stop and remove containers (data persists in volumes)
docker compose down

# Stop and remove containers + volumes (DELETES ALL DATA!)
docker compose down -v

# Stop and remove containers + images
docker compose down --rmi all

Viewing Status & Logs

# List all services and their status
docker compose ps

# View logs of all services
docker compose logs

# Follow logs in real-time
docker compose logs -f

# View logs for specific service
docker compose logs postgres
docker compose logs -f kafka

# View last 100 lines
docker compose logs --tail=100

# View logs with timestamps
docker compose logs -t

Restarting Services

# Restart all services
docker compose restart

# Restart specific service
docker compose restart postgres

# Restart and view logs
docker compose restart postgres && docker compose logs -f postgres

Executing Commands in Containers

# Execute command in running container
docker compose exec postgres psql -U taskuser -d taskdb

# Execute as specific user
docker compose exec -u root postgres bash

# Start a bash shell in container
docker compose exec postgres bash
docker compose exec kafka bash

# Run one-off command (creates new container)
docker compose run postgres psql -U taskuser

Service Management

Building & Pulling

# Build or rebuild services
docker compose build

# Build specific service
docker compose build task-service

# Pull latest images
docker compose pull

# Build without cache
docker compose build --no-cache

Scaling Services

# Scale a service to multiple instances
docker compose up -d --scale kafka=3

# Scale multiple services
docker compose up -d --scale web=3 --scale worker=2

Configuration

# Validate docker-compose.yml syntax
docker compose config

# View the actual configuration (with variable substitution)
docker compose config --resolve-image-digests

# List services defined in compose file
docker compose config --services

Volume & Network Management

Volumes

# List volumes
docker volume ls

# Inspect a volume
docker volume inspect taskmanagement_postgres_data

# Remove unused volumes
docker volume prune

# Remove specific volume (service must be stopped)
docker volume rm taskmanagement_postgres_data

Networks

# List networks
docker network ls

# Inspect network
docker network inspect taskmanagement_app-network

# Remove unused networks
docker network prune

Troubleshooting

Health Checks

# Check container health status
docker compose ps

# Inspect container details
docker inspect task-postgres

# View health check logs
docker inspect task-postgres | grep -i health

Resource Usage

# View resource usage (CPU, Memory)
docker stats

# View for specific service
docker stats task-postgres

Debugging

# View container processes
docker compose top

# View port mappings
docker compose port postgres 5432

# Check events
docker compose events

# Pause all services
docker compose pause

# Unpause all services
docker compose unpause

Clean Up Commands

Remove Everything (Nuclear Option)

# Stop and remove containers, networks
docker compose down

# Stop and remove containers, networks, volumes
docker compose down -v

# Stop and remove containers, networks, volumes, images
docker compose down -v --rmi all

# Remove all unused Docker resources system-wide
docker system prune -a --volumes

Selective Cleanup

# Remove stopped containers
docker compose rm

# Remove stopped containers without confirmation
docker compose rm -f

# Remove unused images
docker image prune

# Remove dangling volumes
docker volume prune

Environment & Variables

Environment Files

# Use specific env file
docker compose --env-file .env.prod up -d

# Override compose file
docker compose -f docker-compose.yml -f docker-compose.prod.yml up -d

View Environment Variables

# Show environment variables of a service
docker compose exec postgres env

# Run with environment variable override
docker compose run -e DEBUG=1 web

Useful Combinations

Complete Restart

# Stop, remove, rebuild, and start fresh
docker compose down && docker compose up -d --build

Quick Troubleshoot

# Check status and logs
docker compose ps && docker compose logs --tail=50

Fresh Start (Keep Data)

# Restart everything without losing data
docker compose down && docker compose up -d

Fresh Start (Delete Everything)

# Complete wipe and restart
docker compose down -v && docker compose up -d

Monitor Specific Service

# Watch logs and stats
docker compose logs -f postgres & docker stats task-postgres

Project-Specific Quick Commands

For Your Task Management App

# Start everything
docker compose up -d

# View all services
docker compose ps

# Check PostgreSQL
docker compose exec postgres psql -U taskuser -d taskdb

# View Kafka topics
docker compose exec kafka kafka-topics --list --bootstrap-server localhost:9092

# Check MinIO
curl http://localhost:9000/minio/health/live

# View all logs
docker compose logs -f

# Restart just Spring Boot (if containerized later)
docker compose restart task-service

# Clean restart (keeps data)
docker compose down && docker compose up -d

# Nuclear option (deletes everything)
docker compose down -v && docker compose up -d

Tips & Best Practices

  1. Always use -d for production/development (runs in background)
  2. Check logs frequently with docker compose logs -f
  3. Use docker compose ps to quickly check service status
  4. Before deleting volumes (-v flag), ensure you have backups
  5. Use docker compose config to validate your compose file
  6. Name your containers in compose file for easier reference
  7. Health checks are your friends - use them to ensure services are ready
  8. Use networks to isolate services
  9. Resource limits prevent one service from consuming all resources

Common Issues & Fixes

Port Already in Use

# Find what's using the port
lsof -i :5432

# Kill the process or change port in docker-compose.yml
ports:
  - "5433:5432"

Service Won't Start

# Check logs
docker compose logs service-name

# Remove and recreate
docker compose rm -f service-name
docker compose up -d service-name

Out of Disk Space

# Clean up everything unused
docker system prune -a --volumes

# Check disk usage
docker system df

Networking Issues

# Recreate network
docker compose down
docker network prune
docker compose up -d

Keyboard Shortcuts in Logs

  • Ctrl+C - Stop following logs
  • Ctrl+Z - Suspend process
  • Ctrl+D - Exit interactive shell

File Locations (Mac)

  • Compose files: Usually in project root
  • Volumes: ~/Library/Containers/com.docker.docker/Data/
  • Logs: View via Docker Desktop or docker compose logs