AWS Cloud Practitioner Study Session One

December 26, 2025

I am taking the AWS Cloud Practitioner Exam in approximately nine days and want to ensure I am prepared. This series will serve as non-exhaustive note taking for the information that I am internalizing as I go.

ChatGPT Summary:

AWS Certified Cloud Practitioner – S3 & Storage Summary

How to Think About AWS Exam Questions

Many Practitioner questions are intentionally verbose and scenario-based (e.g., “Your customer is looking to…”). The key tactic is:

• Ignore distractions and identify the core goal:
  • Lowest cost?
  • Fast access?
  • Long-term retention?
  • Compliance?
  • Automation?
• Once the goal is clear, map it to the AWS service or storage class that best fits that requirement.

AWS exam questions focus less on memorization and more on choosing the best tool for the situation.

Amazon S3: Core Concepts

What S3 Is

• Amazon S3 (Simple Storage Service):
  • Object storage (not block or file storage)
  • Designed for 11 nines of durability (99.999999999%)
  • Highly available and infinitely scalable
• Common use cases:
  • Application assets
  • Backups
  • Media storage
  • Logs
  • Data lakes

Consistency Model (High-Yield Topic)

• S3 is strongly consistent for all operations:
  • PUT
  • GET
  • DELETE
  • LIST

What this means in practice:

• After a successful PUT (200 OK), data is immediately readable.
• After a DELETE (204 No Content), the object is immediately unavailable (404 Not Found).
• No retries, delays, or stale reads are required.
• Treat S3 like a predictable, strongly consistent distributed system.

⚠️ Exam tip: Any answer suggesting “eventual consistency workarounds” is outdated.

S3 Storage Classes

S3 Standard

• Best for: Frequently accessed data
• Characteristics:
  • Highest storage cost
  • No retrieval fees
  • Millisecond access
• Examples:
  • Active applications
  • Website content
  • Frequently accessed objects

S3 Standard–Infrequent Access (S3-IA)

• Best for: Data accessed occasionally but needing fast retrieval
• Characteristics:
  • Lower storage cost than S3 Standard
  • Same millisecond access speed
  • Retrieval fees apply
  • Minimum storage duration of 30 days
• Examples:
  • Backups
  • Disaster recovery copies

📝 Exam clue: “Rarely accessed but must be available immediately” → S3-IA

Amazon S3 Glacier (Archival Storage)

Glacier is designed for long-term archival data that is rarely accessed.

Glacier Storage Tiers

1. Glacier Instant Retrieval
   • Millisecond access
   • Lowest-cost option with instant access
   • For rarely accessed but occasionally needed archives
2. Glacier Flexible Retrieval
   • Retrieval time: minutes to hours
   • Balanced cost vs. access speed
3. Glacier Deep Archive
   • Retrieval time: hours
   • Lowest-cost storage in AWS
   • Ideal for compliance and regulatory data

📝 Exam clue: “Lowest cost,” “long-term retention,” “rare access” → Glacier (often Deep Archive)

Lifecycle Policies: Automating Cost Optimization

S3 Lifecycle Policies automatically transition objects between storage classes based on age.

Example Lifecycle Strategy

• Days 0–30 → S3 Standard
• Days 31–60 → S3 Standard-IA
• Days 61–90 → Glacier
• After 2 years → Auto-delete

Why this matters on the exam:

• Demonstrates:
  • Cost optimization
  • Automation
  • AWS best practices
• If a question mentions:
  • “Automatically move data”
  • “As data ages”
  • “Reduce storage costs over time” → The correct answer usually includes Lifecycle Policies.

Cost vs. Access Speed Comparison

Golden rule:

• Faster access → Higher cost
• Less frequent access → Lower cost

Final Exam Takeaways

• Always identify the customer’s primary goal first.
• S3 is:
  • Object storage
  • Highly durable
  • Strongly consistent
• Choose storage classes based on:
  • Access frequency
  • Retrieval speed requirements
  • Cost sensitivity
• Glacier is for archival, not frequently restored backups.
• Lifecycle policies are the AWS-preferred way to manage data over time.

Study materials:

• Free Code Camp Preparation
• AWS Certified Solutions Architect Practice Tests
• AWS Cloud Practitioner Essentials
• AWS Documentation
  • What is Cloud Computing?
  • Shared Responsibility Model
  • Regions and Availability Zones
• ChatGPT

Raw Input Notes:

Tactics

• Some questions are structured as “Your customer is looking to xyz,” and then proceed to be very wordy, likely meant to throw the reader off from what the customer is looking to accomplish. Remember for this style of question to come back to “What’s the goal of the customer?” before answering.

S3-IA Storage

• IA: Infrequent Access.
• Designed for data that you don’t access often, still need to retrieve quickly.
• Storage costs for S3 Standard are higher than S3-IA.
• Access speed remains the same.
• S3 Standard use cases: Active apps, content
• S3-IA use cases: Backups, disaster recovery

Glacier Storage

• Long term data you rarely access
• 3 tiers: Glacier Instant Retrieval, Glacier Flexible Retrieval, Glacier Deep Archive
• Much cheaper than S3-IA
• Slower Access (minutes to hours)

Automation Timeframe Example

• 30 days -> S3
• 60 days -> S3-IA
• 90 days -> Glacier (Ex. Compliance)
• 2 yrs - Auto-delete

As of today, unlike some of the legacy study material, S3 is strongly consistent for all HTTP methods.

What does this mean, in practice?

• Before consistency developers had to do sleeps / retries, stale reads, edge cases, etc. )Think like database consistency… think of it like a distributed database) With strong consistency, S3 behaves predictably.
• Ex. PUT -> 200 OK, GET -> Returns content
• Ex. DELETE -> 204 No Content -> 404 Not Found immediately