DEV Community: Leo Chen

AWS Certified Cloud Practitioner: My Personal Cheatsheet & Exam Tips

Leo Chen — Thu, 20 Mar 2025 04:14:55 +0000

I’m super happy to share that I passed the AWS Certified Cloud Practitioner exam! In this post, I’ll go over the resources I used and my personal experience preparing for it. Plus, I’ll share my cheat sheet (which I put together myself) to help anyone else studying for the exam.

My Background

Before taking the exam, I was a graduate IT student and had been working as a full-stack engineer at a startup for about six months. I had some experience with CI/CD and had used AWS services like EC2 and S3, but not extensively. Because of this background, I was able to understand most of the concepts covered in online lectures, but I still had to memorize a lot of AWS services and details.

Study Materials

I used Stephane Maarek’s "Ultimate AWS Certified Cloud Practitioner" course on Udemy, along with his practice exams.

This course covers everything you need for the exam. In my opinion, the practice exams were actually harder than the real exam. If you can pass those, you’ll probably be fine in the actual test. The practice questions also cover all the critical topics, and I even saw a few questions that were exactly the same in the real exam!

My Study Plan

✅ 10 days – Studied for about 3 hours per day

Watched the online course
Took notes

✅ 3 days before the exam

Focused on practice exams

My Cheat Sheet

AWS Services

1. Compute Services

Service Name	Purpose	Important Notes
EC2	Virtual servers in AWS	Supports different instance types (General, Compute, Memory, Storage optimized)
ECS	Docker container orchestration	Requires EC2 instances
EKS	Managed Kubernetes	Supports Kubernetes workloads
Fargate	Serverless containers	No need to manage EC2 instances
Lambda	Serverless computing	Event-driven, max execution time of 30 min
Batch	Batch processing at scale	Manages EC2 & ECS for processing
Lightsail	Simplified cloud computing	Good for beginners, no auto-scaling
AWS WaveLength	AWS infrastructure at edge of 5G networks	Low-latency applications at the edge

2. Storage Services

Service Name	Purpose	Important Notes
S3	Object storage	Supports versioning, lifecycle policies, replication
EBS	Block storage for EC2	Network drive for EC2, locked to AZ
EFS	Shared file system	Works across multiple EC2 instances
Amazon FSx	Managed file system	Supports Windows File Server and Lustre
Glacier	Archive storage	Designed for long-term backup
AWS Backup	Centralized backup solution	Supports cross-region and cross-account backup
AWS Storage Gateway	Hybrid storage solution	Bridges on-premises data with AWS

3. Networking & Content Delivery

Service Name	Purpose	Important Notes
VPC	Virtual Private Cloud	Defines networking boundaries
Security Groups	EC2 firewall	Controls inbound/outbound traffic
NACL	Network Access Control List	Stateless, works at subnet level
Route 53	DNS management	Supports routing policies: Simple, Weighted, Latency-based, Failover
CloudFront	Content Delivery Network (CDN)	Caches content at edge locations
Global Accelerator	Traffic routing optimization	Uses AWS backbone for low latency
Elastic Load Balancer (ELB)	Distributes traffic	Application, Network, and Gateway Load Balancer types
Direct Connect	Private network connection	Secure connection between on-premises and AWS
Transit Gateway	Connect multiple VPCs	Scales better than VPC Peering
AWS PrivateLink	Private access to AWS services	Avoids public internet
Site-to-Site VPN	Connects on-premises network to AWS	Uses a VPN tunnel
AWS Client VPN	Securely connect remote users	Uses OpenVPN
AWS Certificate Manager (ACM)	Provision and manage SSL/TLS certificates	Simplifies certificate management for AWS resources

4. Security, Identity & Compliance

Service Name	Purpose	Important Notes
IAM	Identity and Access Management	Controls user permissions, supports MFA
IAM Identity Center (SSO)	Single Sign-On	One login for multiple AWS accounts
AWS KMS	Key Management Service	Encrypts data using managed keys
AWS Secrets Manager	Securely store secrets	Supports automatic rotation
WAF	Web Application Firewall	Protects against Layer 7 attacks
Shield	DDoS protection	Standard is free, Advanced is paid
GuardDuty	Threat detection	Uses machine learning for anomaly detection
Macie	Sensitive data discovery	Finds PII data in S3
AWS Config	Compliance tracking	Monitors AWS resource configurations
AWS Security Hub	Central security tool	Aggregates findings from GuardDuty, Macie, etc.
AWS Artifact	Compliance documentation	Provides compliance reports
AWS Abuse	Report AWS misuse	Detects suspicious activity
AWS Audit Manager	Automated compliance assessments	Tracks security audits
AWS Detective	Security investigation and forensic analysis	To identify root cause
AWS Firewall Manager	Centrally manages security rules	Works across multiple AWS accounts
AWS Incident Manager	Manages and automates incident response	Coordinates response to operational incidents

5. Databases

Service Name	Purpose	Important Notes
RDS	Managed relational database	Supports MySQL, PostgreSQL, Aurora, etc.
Aurora	High-performance RDS	AWS version of MySQL/PostgreSQL
DynamoDB	NoSQL key-value database	Serverless, auto-scaling
ElastiCache	In-memory caching	Supports Redis & Memcached
Redshift	Data warehousing	OLAP, columnar storage, MPP
Neptune	Graph database	Used for social networks
Timestream	Time-series database	Optimized for IoT data
QLDB	Immutable ledger database	Tracks changes over time
DocumentDB	Managed MongoDB	Compatible with MongoDB API
DMS	Database Migration Service	Supports homogeneous and heterogeneous migrations

6. Analytics & AI/ML

Service Name	Purpose	Important Notes
Athena	Query S3 data with SQL	Serverless, pay-per-query
Glue	ETL service	Extract, transform, load data
Kinesis	Real-time big data streaming	Supports logs, video streaming
QuickSight	Business Intelligence	Dashboards and visualizations
Rekognition	Image and video analysis	Detects faces, objects, and text
Comprehend	Natural Language Processing (NLP)	Analyzes text sentiment
Lex	Chatbot service	Powers Amazon Alexa
Polly	Text-to-speech	Converts text into human-like speech
SageMaker	Machine Learning platform	Train, deploy ML models
Kendra	Document search service	Enterprise search service
Personalize	Real-time personalized recommendations	Customized user experiences
Amazon EMR	Managed Hadoop framework	For Big Data processing

7. Developer & Management Tools

Service Name	Purpose	Important Notes
CloudFormation	Infrastructure as Code	Uses YAML/JSON templates
CodeCommit	AWS version of GitHub	Stores source code
CodeBuild	CI/CD build service	Compiles source code, runs tests
CodeDeploy	Automated deployments	Deploys code to EC2, Lambda, etc.
CodePipeline	CI/CD automation	Orchestrates software deployment
CloudWatch	Monitoring & logging	Tracks metrics and logs
CloudTrail	API activity logging	Tracks user actions for auditing, regional and organization trail options
X-Ray	Visual analysis distributed system	For debugging microservices
CodeGuru	Code review	ML-powered service
Step Functions	Serverless workflow automation	Coordinates Lambda executions

8. Migration & Hybrid Services

Service Name	Purpose	Important Notes
AWS Migration Hub	Centralized migration tracking	Integrates with DMS and MGN
Application Migration Service (MGN)	Lift-and-shift migration	Continuous replication
AWS DataSync	Transfer data to AWS	Supports S3, EFS, FSx
AWS Snowball	Physical data transfer	Large-scale data migration
AWS Outposts	Hybrid cloud infrastructure	AWS services on-premises
AWS Ground Station	Satellite data processing	Management and control of satellite communications

9. Communication & Messaging

Service Name	Purpose	Important Notes
SNS	Notification service	Pub/Sub model, supports SMS, email
SQS	Queueing service	FIFO and Standard queues
MQ	Managed message broker	Supports RabbitMQ, ActiveMQ

10. Business & Productivity

Service Name	Purpose	Important Notes
WorkSpaces	Virtual desktop infrastructure	Windows & Linux remote desktops
AppStream 2.0	Application streaming	Runs applications via web browser
Chime	Video conferencing	AWS alternative to Zoom
Amazon Pinpoint	Customer communication	Sends targeted notifications
SES	Simple Email Service	Sends transactional and marketing emails
AWS IQ	Freelancer platform	Connects customers with AWS experts

11. Cost Management

Service Name	Purpose	Important Notes
AWS Cost Explorer	Cost tracking & forecasting	Analyzes spending trends
AWS Budgets	Budget alerts	Monitors cost thresholds
AWS Pricing Calculator	Estimates AWS costs	Provides cost projections
AWS Compute Optimizer	Resource optimization	Suggests efficient instance types

12. Governance & Account Management

Service Name	Purpose	Important Notes
AWS Organizations	Multi-account management	Supports consolidated billing
AWS Service Catalog	Pre-approved cloud services	Helps manage access to services
AWS Control Tower	Multi-account governance	Automates account setup

AWS & Cloud Concepts

1. Global Infrastructure

Component	Description	Key Points
Regions	Geographic areas	Isolated from each other, each with multiple AZs
Availability Zones (AZs)	Physically separated data centers	Connected with low-latency links, isolated from failures
Edge Locations	CDN endpoints	Used by CloudFront, closer to users than regions
Local Zones	Infrastructure extensions	Brings select services closer to population centers
Wavelength Zones	5G infrastructure	Embedded in telecom provider networks
Outposts	On-premises AWS	Brings AWS to your data center

2. Cloud Computing Models

IaaS (Infrastructure as a Service): EC2, EBS, VPC
PaaS (Platform as a Service): Elastic Beanstalk
SaaS (Software as a Service): AWS WorkSpaces, Amazon Connect

3. AWS Pricing Models

On-Demand: Pay for what you use (EC2, RDS, Lambda)
Reserved Instances: Commit to a certain period for discounts
Spot Instances: Low-cost, can be terminated anytime
Savings Plans: Flexible pricing for compute usage

4. AWS Shared Responsibility Model

AWS is responsible for: Security of the cloud (infrastructure, hardware)
Customer is responsible for: Security in the cloud (IAM, app data, OS updates)

5. Scalability & Availability

Vertical Scaling: Increasing instance size (CPU, RAM)
Horizontal Scaling: Increasing the number of instances
High Availability: Deploying across multiple AZs/Regions

6. Networking in AWS

Public Subnet: Accessible from the internet
Private Subnet: No direct internet access
Internet Gateway: Enables internet access for public subnet
NAT Gateway: Enables internet access for private subnet
Transit Gateway: Centralized network hub for multiple VPCs

7. Disaster Recovery Strategies

Backup & Restore: Store backups in S3 or Glacier
Pilot Light: Minimal infrastructure running at all times
Warm Standby: Running infrastructure at reduced capacity
Multi-Site: Full replication across regions

8. Well-Architected Framework (6 Pillars)

Pillar	Focus
Operational Excellence	Effective system operations and continuous improvement
Security	Protecting assets while delivering business value
Reliability	System recovery and disruption mitigation
Performance Efficiency	Optimal resource utilization
Cost Optimization	Maximum value at minimum cost
Sustainability	Reducing environmental impact

9. Cloud Adoption Framework (6 Perspectives)

Perspective	Focus
Business	Aligning cloud investments with business transformation
People	Culture, leadership, and workforce considerations
Governance	Managing cloud initiatives effectively
Platform	Building scalable cloud infrastructure
Security	Ensuring data protection and compliance
Operations	Delivering reliable cloud services

10. Support Plans

Support Plan	Intended For	AWS Trusted Advisor	Cloud Support Engineers	Infrastructure Event Management
Basic	Individual users	Basic checks only	No access	Not included
Developer	Testing & development	Basic checks only	Business hours email	Not included
Business	Production workloads	Full access	24/7 phone, email & chat	Not included
Enterprise	Mission-critical workloads	Full access	24/7 support with TAM	Included

11. S3 Storage Classes

Storage Class	Purpose	Min Storage Duration	Use Cases
S3 Standard	General purpose	None	Frequent access, websites, content
S3 Intelligent-Tiering	Unknown access patterns	None	Unpredictable access patterns
S3 Standard-IA	Infrequent access	30 days	Backups, disaster recovery
S3 One Zone-IA	Non-critical data	30 days	Secondary backups, recreatable data
S3 Glacier Instant Retrieval	Archive with instant access	90 days	Archives needing immediate retrieval
S3 Glacier Flexible Retrieval	Archive with flexible retrieval	90 days	Archives with minutes to hours retrieval
S3 Glacier Deep Archive	Long-term archive	180 days	Compliance, long-term retention

12. EC2 Instance Types

Pricing Model	Description	Best For	Commitment	Savings
On-Demand	Pay per use	Short-term workloads	None	None
Reserved	Reserved capacity	Steady applications	1 or 3 years	Up to 72% off
Spot	Unused capacity	Batch processing	None (2 min notice)	Up to 90% off
Dedicated Host	Physical server	Complex licensing	On-Demand/Reserved	Varies
Savings Plans	Committed usage	Flexible compute	1 or 3 years	Up to 72% off

Final Thoughts

If you’re preparing for the AWS Certified Cloud Practitioner, here is my tips for you:

Follow a structured course
Take practice exams
Don't overthink it — The exam is designed to test your foundational knowledge, not trick you with super technical details
Take breaks — Information overload is real. I found that taking short breaks helped me retain more than continuous studying.

Hope this helps, and good luck to anyone taking the exam!

Deploy Your Personal Website for Free: A Step-by-Step Guide with Next.js and Render

Leo Chen — Sat, 22 Feb 2025 14:52:12 +0000

Have you ever imagined having your own website on the internet with a valid HTTPS URL? Recently, I created my own portfolio website and a small business website for a friend. In this tutorial, I'll show you how I did it in just a few minutes. It's super easy, free, and perfect for anyone who wants to showcase their work online!

Why Have a Personal Website?

As a software engineer, having a portfolio website is essential. It allows you to showcase the projects you've built, highlight your experience, and make a great impression—especially if you're looking for new opportunities. A basic portfolio website can be a static website, meaning it doesn't require a backend. That makes deployment much easier since we only need to focus on building the frontend and finding a place to host it.

Static vs Dynamic Websites: What's the Difference?

A dynamic website is one where the content changes based on user interactions or data from a backend server. Examples include social media platforms, e-commerce stores, and dashboards.

A static website, on the other hand, consists of pre-built HTML, CSS, and JavaScript files that are served directly to the user without requiring backend processing. Static websites are faster, cheaper to host, and ideal for portfolios, blogs, and landing pages.

Why Render?

Render is a modern cloud platform that offers an impressive free tier for static website hosting. It provides automated deployments, SSL certificates, and CDN distribution out of the box. Unlike traditional hosting services, Render simplifies the deployment process by connecting directly to your GitHub repository and automatically rebuilding your site when you push changes.

Prerequisites

Basic knowledge of React/Next.js
A GitHub account
Your website code ready in a repository

Step-by-Step Deployment Guide

Step1. Prepare Your Repository

Make sure your Next.js project is ready for static deployment. You can use my template as a starting point: Next.js Website Template

Step2. Set Up Render Account

Visit Render and sign up for a free account

Step 3: Create a New Static Website

On your Render dashboard, click + Add New > Static Site.

Step 4: Connect GitHub

Select GitHub as your Git provider and authorize Render to access your repositories.

Step 5: Select the Repository to Deploy

Choose the repository where your website code is stored.

Step 6: Configure the Deployment

Site Name: Choose a unique name (Render will generate a URL in the format: https://.onrender.com).
Build Command: npm install && npm run build
Publish Directory: out (for Next.js static export)

Tip:: Once the site name is set, it cannot be changed, so pick wisely!

Step 7: Deploy Your Website

Click Deploy and let Render handle the rest. The system will automatically build and deploy your site. Once it's done, you'll see the message "Your site is live!" 🎉

Troubleshooting

If you encounter issues:

Check your build logs in the Render dashboard
Verify your build command and publish directory

Conclusion

That's it! You now have your own website live on the internet, completely free. Whether it's a portfolio, blog, or small business site, Render makes it incredibly easy to deploy static websites with Next.js. If you have any questions or improvements, feel free to drop a comment.

References

Render Docs: Deploying Next.js Apps

Debugging Google Chrome Extensions Locally: A Quick & Easy Guide

Leo Chen — Tue, 18 Feb 2025 07:38:22 +0000

Google Chrome is one of the most popular browsers in the world. It offers powerful extensions that let developers enhance the browsing experience. From game hacks to productivity tools — if you can dream it, you can build it. And the best part? It’s surprisingly easy to get started.

In this tutorial, I’ll walk you through the simple steps to debug your own Chrome extension.

Before we dive in, check out my project, Face Blindness Saver — a Chrome extension that identifies celebrities in YouTube videos. You can use it to follow along with this guide today!

Step 1: Open the Chrome Extension Management Page

Open Google Chrome.
In the address bar, type: chrome://extensions and hit Enter.
Toggle on Developer mode in the top-right corner.

Step 2: Load Your Extension

Click the Load unpacked button.
Navigate to your extension’s folder and select it.
Chrome will instantly load the extension, and you’ll see it appear on the page.

Step 3: Run & Debug

Congratulations! Your extension should now appear in the list of installed extensions. The extension will automatically start running. Now you can debug your extension just like any webpage — set breakpoints, log messages, and watch the magic happen.

And that's it! You're now ready to test and debug your Chrome extension!