Basics of Docker on RamNode

Server Requirements

• • RamNode VPS (1GB+ RAM recommended)
• • Ubuntu 22.04/24.04 or CentOS
• • Root access to server
• • SSH client

Knowledge Requirements

• • Basic Linux command line
• • Understanding of containerization
• • SSH connection skills
• • Basic Docker concepts

💰 Exceptional Price-to-Performance Ratio

RamNode's pricing starts at just a few dollars per month for VPS instances with sufficient resources to run multiple lightweight containers. Entry-level plans typically include 1GB RAM, 20GB SSD storage, and generous bandwidth allocations.

⚡ SSD Storage Across All Plans

Unlike many budget providers that still rely on traditional hard drives, RamNode provides SSD and NVMe storage across their entire range. This translates to faster container startup times, improved I/O performance, and better overall application responsiveness.

🌍 Multiple Data Center Locations

With locations in the US, Netherlands, and other strategic regions, you can deploy containers closer to your users, reducing latency and improving user experience.

🔧 KVM Virtualization

RamNode uses KVM virtualization, providing better isolation and performance compared to OpenVZ containers that many budget providers use. This ensures your Docker containers run in a more predictable environment.

ssh root@your-server-ip

sudo apt update && sudo apt upgrade -y sudo apt install curl wget git htop unzip -y

curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo gpg --dearmor -o /usr/share/keyrings/docker-archive-keyring.gpg

echo "deb [arch=amd64 signed-by=/usr/share/keyrings/docker-archive-keyring.gpg] https://download.docker.com/linux/ubuntu $(lsb_release -cs) stable" | sudo tee /etc/apt/sources.list.d/docker.list > /dev/null

sudo apt update sudo apt install docker-ce docker-ce-cli containerd.io docker-compose-plugin -y

sudo usermod -aG docker $USER

docker --version docker run hello-world

{
 "log-driver": "json-file",
 "log-opts": {
 "max-size": "10m",
 "max-file": "3"
 },
 "storage-driver": "overlay2",
 "default-ulimits": {
 "nofile": {
 "hard": 65536,
 "soft": 65536
 }
 }
}

sudo sed -i 's/GRUB_CMDLINE_LINUX=""/GRUB_CMDLINE_LINUX="cgroup_enable=memory swapaccount=1"/' /etc/default/grub sudo update-grub sudo reboot

# Instead of this:
# FROM node:16
# Use this:
FROM node:16-alpine
WORKDIR /app
COPY package*.json ./
RUN npm ci --only=production && npm cache clean --force
COPY . .
EXPOSE 3000
CMD ["node", "index.js"]

# Build stage
FROM node:16-alpine AS builder
WORKDIR /app
COPY package*.json ./
RUN npm ci
COPY . .
RUN npm run build
# Production stage
FROM node:16-alpine AS production
WORKDIR /app
COPY package*.json ./
RUN npm ci --only=production && npm cache clean --force
COPY --from=builder /app/dist ./dist
EXPOSE 3000
CMD ["node", "dist/index.js"]

FROM node:16-alpine
WORKDIR /app
# Copy package files first (changes less frequently)
COPY package*.json ./
RUN npm ci --only=production
# Copy application code last (changes more frequently)
COPY . .
EXPOSE 3000
CMD ["node", "index.js"]

# Limit container to 512MB RAM and 0.5 CPU cores docker run -d --name myapp --memory=512m --cpus="0.5" myapp:latest

version: '3.8'
services:
 web:
 image: myapp:latest
 deploy:
 resources:
 limits:
 memory: 512M
 cpus: '0.5'
 reservations:
 memory: 256M
 cpus: '0.25'

# Monitor all container resource usage docker stats # Monitor specific container docker stats container_name # Get detailed container information docker inspect container_name

version: '3.8'
services:
 nginx:
 image: nginx:alpine
 ports:
 - "80:80"
 - "443:443"
 volumes:
 - ./nginx.conf:/etc/nginx/nginx.conf:ro
 - ./ssl:/etc/nginx/ssl:ro
 deploy:
 resources:
 limits:
 memory: 128M
 cpus: '0.2'
 restart: unless-stopped
 app:
 build: .
 environment:
 - NODE_ENV=production
 - DATABASE_URL=postgresql://user:pass@db:5432/myapp
 deploy:
 resources:
 limits:
 memory: 512M
 cpus: '0.5'
 restart: unless-stopped
 depends_on:
 - db
 db:
 image: postgres:13-alpine
 environment:
 - POSTGRES_DB=myapp
 - POSTGRES_USER=user
 - POSTGRES_PASSWORD=pass
 volumes:
 - postgres_data:/var/lib/postgresql/data
 deploy:
 resources:
 limits:
 memory: 256M
 cpus: '0.3'
 restart: unless-stopped
volumes:
 postgres_data:

version: '3.8'
services:
 auth-service:
 image: auth-service:alpine
 ports:
 - "3001:3000"
 environment:
 - JWT_SECRET=${JWT_SECRET}
 deploy:
 resources:
 limits:
 memory: 256M
 cpus: '0.25'
 api-gateway:
 image: api-gateway:alpine
 ports:
 - "8080:8080"
 environment:
 - AUTH_SERVICE_URL=http://auth-service:3000
 - USER_SERVICE_URL=http://user-service:3000
 deploy:
 resources:
 limits:
 memory: 256M
 cpus: '0.25'
 depends_on:
 - auth-service
 - user-service
 user-service:
 image: user-service:alpine
 environment:
 - DATABASE_URL=${DATABASE_URL}
 deploy:
 resources:
 limits:
 memory: 256M
 cpus: '0.25'

Image Size Optimization

• • Use .dockerignore files to exclude unnecessary files from build context
• • Remove package managers and build tools from production images
• • Combine RUN commands to reduce layers
• • Use specific package versions to avoid cache invalidation

Efficient Data Management

# Use named volumes for persistent data
volumes:
 app_data:
 driver: local
 driver_opts:
 type: none
 o: bind
 device: /opt/app-data
# Implement log rotation
logging:
 driver: "json-file"
 options:
 max-size: "10m"
 max-file: "3"

Automated Cleanup

Implement automated cleanup to prevent disk space issues:

#!/bin/bash
# cleanup-docker.sh
# Remove unused containers
docker container prune -f
# Remove unused images
docker image prune -f
# Remove unused volumes
docker volume prune -f
# Remove unused networks
docker network prune -f
# Schedule with cron
# 0 2 * * * /opt/scripts/cleanup-docker.sh

# Create non-root user
RUN addgroup -g 1001 -S nodejs
RUN adduser -S nextjs -u 1001
# Switch to non-root user
USER nextjs

networks:
 frontend:
 driver: bridge
 backend:
 driver: bridge
 internal: true
services:
 web:
 networks:
 - frontend
 app:
 networks:
 - frontend
 - backend
 db:
 networks:
 - backend

# Initialize swarm on manager node
docker swarm init --advertise-addr <manager-ip>
# Join worker nodes
docker swarm join --token <worker-token> <manager-ip>:2377
# Deploy stack with replicas
docker service create --replicas 3 --name web-service nginx:alpine

version: '3.8'
services:
 traefik:
 image: traefik:v2.9
 command:
 - --api.dashboard=true
 - --providers.docker=true
 - --entrypoints.web.address=:80
 ports:
 - "80:80"
 - "8080:8080"
 volumes:
 - /var/run/docker.sock:/var/run/docker.sock:ro
 app:
 image: myapp:latest
 deploy:
 replicas: 3
 labels:
 - "traefik.enable=true"
 - "traefik.http.routers.app.rule=Host(`myapp.example.com`)"

Memory Issues

Disk Space Issues

Performance Issues

Networking Problems