Docker Command Line Tips - Complete Guide

# Run a container
docker run -d --name myapp nginx:latest

# Run with port mapping
docker run -d -p 8080:80 --name web nginx:latest

# Run with environment variables
docker run -d -e NODE_ENV=production --name app node:18

# Run with volume mount
docker run -d -v /host/path:/container/path --name data alpine:latest

# Start/stop containers
docker start myapp
docker stop myapp
docker restart myapp

# Remove container
docker rm myapp

# Remove running container (force)
docker rm -f myapp

# List running containers
docker ps

# List all containers (including stopped)
docker ps -a

# List containers with custom format
docker ps --format "table {{.Names}}\t{{.Status}}\t{{.Ports}}"

# Inspect container details
docker inspect myapp

# View container logs
docker logs myapp

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

# View last N lines of logs
docker logs --tail 100 myapp

# Show container resource usage
docker stats myapp

# Show all containers stats
docker stats

# Build image from Dockerfile
docker build -t myapp:latest .

# Build with specific Dockerfile
docker build -f Dockerfile.prod -t myapp:prod .

# Build with build arguments
docker build --build-arg NODE_ENV=production -t myapp:prod .

# Pull image from registry
docker pull nginx:latest

# Push image to registry
docker push myapp:latest

# Tag image
docker tag myapp:latest myregistry.com/myapp:v1.0

# List images
docker images

# List images with custom format
docker images --format "table {{.Repository}}\t{{.Tag}}\t{{.Size}}"

# Remove image
docker rmi myapp:latest

# Remove unused images
docker image prune

# Remove all unused images (including tagged)
docker image prune -a

# Multi-stage build example
FROM node:18-alpine AS base
WORKDIR /app
COPY package*.json ./

FROM base AS deps
RUN npm ci --only=production

FROM base AS build
RUN npm ci
COPY . .
RUN npm run build

FROM node:18-alpine AS production
WORKDIR /app
COPY --from=deps /app/node_modules ./node_modules
COPY --from=build /app/dist ./dist
COPY package*.json ./
EXPOSE 3000
CMD ["npm", "start"]

# Build specific stage
docker build --target deps -t myapp:deps .

# Build all stages
docker build -t myapp:latest .

# Create volume
docker volume create myvolume

# List volumes
docker volume ls

# Inspect volume
docker volume inspect myvolume

# Remove volume
docker volume rm myvolume

# Remove unused volumes
docker volume prune

# Run container with named volume
docker run -d -v myvolume:/data --name app alpine:latest

# Run container with bind mount
docker run -d -v /host/path:/container/path --name app alpine:latest

# Run container with tmpfs mount
docker run -d --tmpfs /tmp --name app alpine:latest

# Copy files to/from container
docker cp file.txt myapp:/path/to/destination
docker cp myapp:/path/to/file.txt ./local-file.txt

# Create network
docker network create mynetwork

# List networks
docker network ls

# Inspect network
docker network inspect mynetwork

# Remove network
docker network rm mynetwork

# Remove unused networks
docker network prune

# Run container on specific network
docker run -d --network mynetwork --name app1 nginx:latest
docker run -d --network mynetwork --name app2 nginx:latest

# Connect existing container to network
docker network connect mynetwork existing-container

# Disconnect container from network
docker network disconnect mynetwork existing-container

# Create network with custom driver
docker network create --driver bridge --subnet=172.20.0.0/16 mynetwork

# Start services
docker-compose up

# Start services in background
docker-compose up -d

# Start specific service
docker-compose up web

# Build and start
docker-compose up --build

# Stop services
docker-compose down

# Stop and remove volumes
docker-compose down -v

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

# View running services
docker-compose ps

# View logs
docker-compose logs

# Follow logs
docker-compose logs -f

# Execute command in service
docker-compose exec web bash

# Scale service
docker-compose up --scale web=3

# Restart service
docker-compose restart web

# Pull latest images
docker-compose pull

# Run container with memory limit
docker run -d --memory=512m --name app nginx:latest

# Run container with CPU limit
docker run -d --cpus=1.5 --name app nginx:latest

# Run container with both limits
docker run -d --memory=512m --cpus=1.0 --name app nginx:latest

# Run container with memory reservation
docker run -d --memory-reservation=256m --name app nginx:latest

# Run container with ulimits
docker run -d --ulimit nofile=1024:1024 --name app nginx:latest

# Run container with security options
docker run -d --read-only --name app nginx:latest
docker run -d --user=1000:1000 --name app nginx:latest

# Run container with restart policy
docker run -d --restart=unless-stopped --name app nginx:latest

# Execute command in running container
docker exec -it myapp bash

# Execute command as root
docker exec -it --user root myapp bash

# Execute command with specific working directory
docker exec -it -w /app myapp bash

# Attach to container's main process
docker attach myapp

# View container processes
docker exec myapp ps aux

# View container environment variables
docker exec myapp env

# View container network configuration
docker exec myapp ip addr

# View container disk usage
docker exec myapp df -h

# Check container health
docker inspect --format='{{.State.Health.Status}}' myapp

# Add to ~/.bashrc or ~/.zshrc

# Container management
alias dps='docker ps'
alias dpsa='docker ps -a'
alias dstop='docker stop'
alias dstart='docker start'
alias drestart='docker restart'
alias drm='docker rm'
alias drmf='docker rm -f'

# Image management
alias dimg='docker images'
alias drmi='docker rmi'
alias dpull='docker pull'
alias dpush='docker push'
alias dbuild='docker build'

# Logs and inspection
alias dlogs='docker logs'
alias dlogsf='docker logs -f'
alias dinspect='docker inspect'
alias dstats='docker stats'

# Docker Compose shortcuts
alias dc='docker-compose'
alias dcu='docker-compose up'
alias dcd='docker-compose down'
alias dcb='docker-compose up --build'
alias dce='docker-compose exec'
alias dcl='docker-compose logs'
alias dclf='docker-compose logs -f'

# Cleanup commands
alias dclean='docker system prune -f'
alias dcleanall='docker system prune -a -f'
alias dcleanvol='docker volume prune -f'
alias dcleanimg='docker image prune -f'

# Use .dockerignore file
echo "node_modules" >> .dockerignore
echo "*.log" >> .dockerignore
echo ".git" >> .dockerignore
echo "Dockerfile" >> .dockerignore

# Optimize Dockerfile layers
# Bad: Multiple RUN commands
RUN apt-get update
RUN apt-get install -y nodejs
RUN apt-get install -y npm

# Good: Single RUN command
RUN apt-get update && \
    apt-get install -y nodejs npm && \
    apt-get clean && \
    rm -rf /var/lib/apt/lists/*

# Use specific base images
# Bad: node:latest
# Good: node:18-alpine

# Copy package files first for better caching
COPY package*.json ./
RUN npm ci --only=production
COPY . .

# Use multi-stage builds for smaller images
FROM node:18-alpine AS builder
# ... build steps
FROM node:18-alpine AS production
COPY --from=builder /app/dist ./dist

# Run containers as non-root user
RUN addgroup -g 1001 -S nodejs
RUN adduser -S nextjs -u 1001
USER nextjs

# Use read-only filesystem
docker run --read-only --name app nginx:latest

# Limit container capabilities
docker run --cap-drop=ALL --cap-add=NET_BIND_SERVICE --name app nginx:latest

# Use security options
docker run --security-opt=no-new-privileges --name app nginx:latest

# Scan images for vulnerabilities
docker scan nginx:latest

# Use secrets for sensitive data
echo "mysecret" | docker secret create my_secret -
docker service create --secret my_secret nginx:latest

# Use health checks
HEALTHCHECK --interval=30s --timeout=3s --start-period=5s --retries=3 \
  CMD curl -f http://localhost:3000/health || exit 1

# Monitor container resource usage
docker stats --no-stream

# Monitor specific containers
docker stats container1 container2

# Monitor with custom format
docker stats --format "table {{.Container}}\t{{.CPUPerc}}\t{{.MemUsage}}"

# View Docker system information
docker system df

# View Docker system events
docker events

# View Docker system events with filter
docker events --filter container=myapp

# View Docker daemon information
docker info

# View Docker version
docker version

# Monitor Docker Compose services
docker-compose ps
docker-compose top

# Container won't start
docker logs myapp
docker inspect myapp

# Container keeps restarting
docker inspect myapp | grep -A 10 "RestartPolicy"

# Out of disk space
docker system df
docker system prune -a

# Port already in use
docker ps | grep :8080
netstat -tulpn | grep :8080

# Permission denied
docker run --user root myapp
docker exec -it --user root myapp bash

# Network connectivity issues
docker network ls
docker network inspect bridge

# Volume mount issues
docker volume ls
docker volume inspect myvolume

# Image pull failures
docker login
docker pull nginx:latest

# Build failures
docker build --no-cache -t myapp .
docker build --progress=plain -t myapp .

#!/bin/bash
# docker-cleanup.sh - Clean up Docker resources

echo "Cleaning up Docker resources..."

# Stop all running containers
docker stop $(docker ps -q) 2>/dev/null || true

# Remove all containers
docker rm $(docker ps -aq) 2>/dev/null || true

# Remove all images
docker rmi $(docker images -q) 2>/dev/null || true

# Remove all volumes
docker volume rm $(docker volume ls -q) 2>/dev/null || true

# Remove all networks
docker network rm $(docker network ls -q) 2>/dev/null || true

# System cleanup
docker system prune -a -f

echo "Docker cleanup completed!"

#!/bin/bash
# docker-backup.sh - Backup Docker volumes

VOLUME_NAME="myvolume"
BACKUP_FILE="backup-$(date +%Y%m%d-%H%M%S).tar"

echo "Creating backup of volume: $VOLUME_NAME"
docker run --rm -v $VOLUME_NAME:/data -v $(pwd):/backup alpine tar czf /backup/$BACKUP_FILE -C /data .
echo "Backup created: $BACKUP_FILE"