Domain 3: Storage Services

CLF-C02 Exam Domain 3 - Part 2 | 34% of Scored Content

Learning Objectives

By the end of this section, you will be able to:

Understand Amazon S3 core features and storage classes
Compare EBS, EFS, and Instance Store
Identify appropriate storage solutions for use cases
Understand S3 security and replication options
Compare storage costs and performance

Amazon S3 (Simple Storage Service)

Overview

Amazon S3 is object storage built to store and retrieve any amount of data from anywhere.

Key Characteristics

Feature	Description
Object Storage	Store files as "objects" (data + metadata)
Unlimited Storage	No limit on amount of data
High Durability	99.999999999% (11 nines)
High Availability	99.99% availability
Scalable	Virtually unlimited throughput
Low Cost	Pay for what you use

S3 Core Concepts

1. Buckets

Definition: Containers for objects stored in S3.

Bucket Characteristics:

Globally Unique Name: DNS-compliant name
Region: Bucket resides in a specific region
Unlimited Objects: No limit on objects per bucket

Naming Rules:

3-63 characters long
Lowercase letters, numbers, hyphens
Must start with letter or number
Must not end with hyphen
Cannot use xn-- prefix (punycode)

2. Objects

Definition: The fundamental entities stored in S3.

Object Components:

Key: Unique identifier (filename + path)
Data: The actual content
Metadata: Information about the object
Version ID: If versioning is enabled

Example:

Bucket: my-app-bucket
Key: images/2024/photo.jpg
URL: https://my-app-bucket.s3.us-east-1.amazonaws.com/images/2024/photo.jpg

3. S3 Storage Classes

Comparison Table:

Storage Class	Design	Durability	Availability	Minimum Storage	Minimum Charge	Use Case
Standard	Frequent access	99.999999999%	99.99%	None	None	Primary data
Intelligent-Tiering	Auto tiering	99.999999999%	99.9%	30 days	None	Unknown access patterns
Standard-IA	Infrequent access	99.999999999%	99.9%	30 days	30 days	Data accessed less often
One Zone-IA	Infrequent, one AZ	99.999999999%	99.5%	30 days	30 days	Secondary copy
Glacier	Long-term archive	99.999999999%	99.99%	None	90 days	Rarely accessed data
Glacier Deep Archive	Long-term archive	99.999999999%	99.99%	None	180 days	Rarely accessed, lowest cost
Outposts	On-premises	99.999999999%	99.99%	None	None	On-premises storage

Storage Class Decision Tree:

Frequent Access?
  ├─ Yes → S3 Standard
  └─ No
      ├─ Need fastest retrieval (minutes)? → S3 Standard-IA
      ├─ OK with hours? → S3 Glacier Flexible Retrieval
      ├─ OK with 12 hours? → S3 Glacier Deep Archive
      └─ Unknown access pattern? → S3 Intelligent-Tiering

4. S3 Features

Versioning:

Keeps multiple versions of an object
Protects from accidental deletion
Once enabled, cannot be disabled (only suspended)
Use Cases: Backup, data protection, rollback

Lifecycle Policies:

Automatically transition objects between storage classes
Automatically expire/delete objects
Rules: Based on age, prefix, tags
Example: Move to Standard-IA after 30 days, to Glacier after 90 days

Encryption:

Server-Side Encryption:
- SSE-S3: AWS-managed keys
- SSE-KMS: AWS KMS managed keys
- SSE-C: Customer-provided keys
Client-Side Encryption: Encrypt before upload

Replication:

Same-Region Replication (SRR): Copy within region
Cross-Region Replication (CRR): Copy to different region
Requirements: Versioning enabled, source/dest buckets in different regions
Use Cases: Disaster recovery, compliance, latency reduction

Event Notifications:

S3 can publish events to:
- SNS: Send notifications
- SQS: Queue messages
- Lambda: Trigger functions
Events: Object created, removed, or replicated

S3 Select:

Retrieve subset of data from an object
Use Case: Filter large CSV/JSON files
Benefit: Reduce data transfer and cost

Requester Pays:

Bucket owner doesn't pay for data transfer
Requester pays for download and transfer
Use Case: Sharing public datasets

5. S3 Security

Access Control:

Feature	Description
Bucket Policies	JSON-based policies for bucket access
ACLs	Access Control Lists (legacy)
Block Public Access	Prevent public access at account/bucket level
Presigned URLs	Temporary access to private objects
CloudFront OAI	Grant CloudFront access to private content

Bucket Policy Example:

json

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Principal": {"AWS": "arn:aws:iam::123456789012:user/bob"},
      "Action": ["s3:GetObject"],
      "Resource": "arn:aws:s3:::my-bucket/*"
    }
  ]
}

Presigned URLs:

Temporary access (expires after set time)
Use Case: Share private files without making public
CLI: aws s3 presign s3://bucket/key --expires-in 3600

6. S3 Performance

Optimization Tips:

Parallel Uploads: Use multipart upload for large files
S3 Transfer Acceleration: Use CloudFront edge locations
Byte-Range Fetches: Get specific byte ranges
S3 Transfer Acceleration: Faster long-distance transfers

Amazon EBS (Elastic Block Store)

Overview

Amazon EBS provides block-level storage volumes for use with EC2 instances.

Key Characteristics

Feature	Description
Block Storage	Like a hard drive
Persistent	Data survives instance stop/start
Network-Attached	Accessed over the network
Single Instance	One volume attached to one instance
Snapshots	Point-in-time backups to S3

EBS Volume Types

Type	Name	IOPS	Throughput	Use Case	Cost
gp2	General Purpose SSD	Up to 16,000	Up to 250 MB/s	Boot volumes, general workloads	Low
gp3	General Purpose SSD	Up to 16,000	Up to 1,000 MB/s	Cost-effective, flexible	Lowest
io1	Provisioned IOPS SSD	Up to 64,000	Up to 1,000 MB/s	Critical applications, databases	High
io2	Provisioned IOPS SSD	Up to 256,000	Up to 4,000 MB/s	Highest performance, enterprise	Highest
st1	Throughput Optimized HDD	500	Up to 500 MB/s	Big data, data warehouses	Low
sc1	Cold HDD	250	Up to 250 MB/s	File servers, log storage	Lowest

Volume Selection Guide:

Boot Volume or General Workload?
  ├─ Yes → gp3 (best value, predictable performance)
  └─ No
      ├─ Highest performance needed? → io2
      ├─ Big data, throughput needed? → st1
      └─ infrequent access? → sc1

EBS Snapshots

Characteristics:

Incremental backups (only changed data)
Stored in S3
Can create volumes from snapshots
Cross-region copy for DR
Pricing: Storage ($0.05/GB/month), data transfer

Snapshot Lifecycle:

Volume → Snapshot → Copy to S3
              └─ Create new volume from snapshot

EBS Encryption

Enabled at volume creation
Uses AWS KMS
Encrypted snapshots only create encrypted volumes
No performance impact

Amazon EFS (Elastic File System)

Overview

Amazon EFS provides a simple, scalable file system for use with EC2 instances.

Key Characteristics

Feature	Description
File Storage	Like NAS, uses NFS protocol
Shared Access	Multiple instances can access simultaneously
Persistent	Data survives instance termination
Scalable	Grows and shrinks automatically
Pay-per-use	Pay for storage used

EFS Performance

Performance Modes:

Mode	Description	Use Case
General Purpose	Lower latency per operation	Most workloads
Max I/O	Higher latency, higher throughput	Large-scale parallel workloads

Throughput Modes:

Mode	Description	Cost
Bursting	Baseline + credits	Default, lower cost
Provisioned	Fixed throughput	Higher cost, predictable

EFS vs EBS

Feature	EFS	EBS
Access	Multiple instances	Single instance
Size	Up to PB	Up to 16 TB (io2)
Protocol	NFS	Block device
Pricing	Per GB used	Per GB provisioned
Use Case	Shared file system, web serving	Boot volume, database

EFS Storage Classes

Class	Description	Cost
Standard	Frequently accessed data	Higher
Infrequent Access (IA)	Less frequently accessed	Lower
Archive	Rarely accessed	Lowest

Lifecycle policy: Move to IA after 30/60/90/180/270 days of no access

S3 Security Deep Dive

Block Public Access

Account-Level Settings:

Block Public Access (account level)
Block all public access
Block public access to buckets and objects granted through new ACLs
Block public and cross-account access to buckets and objects

Bucket-Level Settings:

Same settings apply to individual bucket

Best Practice: Enable Block Public Access for buckets containing sensitive data

Encryption Options

Encryption Type	Key Management	Use Case
SSE-S3	AWS-managed	Simple encryption
SSE-KMS	KMS-managed	Control key policies, audit
SSE-C	Customer-managed	Full control
DSSE-KMS	Double-layer KMS	Highest security

Encryption in Transit

HTTPS: Secure communication
SSL/TLS: Use presigned URLs with HTTPS
VPC Endpoints: Private connectivity to S3

Exam Tips - Storage Services

High-Yield Topics

S3 Storage Classes:
- Standard = Frequent access
- Standard-IA = Infrequent access, 30-day minimum
- Glacier/Deep Archive = Long-term archive, retrieval time
- Intelligent-Tiering = Auto-tiering based on access
S3 Features:
- Versioning = Multiple versions, cannot be disabled (only suspended)
- Lifecycle policies = Auto transition/delete
- Replication = CRR for DR, SRR for backup
- Encryption = SSE-S3, SSE-KMS, SSE-C
EBS vs Instance Store:
- EBS = Persistent, network-attached
- Instance Store = Ephemeral, on-host
EBS Volume Types:
- gp2/gp3 = General purpose (gp3 has better price/performance)
- io1/io2 = High IOPS, databases
- st1/sc1 = HDD, big data, low cost
EFS:
- File storage, NFS protocol
- Shared across multiple instances
- Auto-scaling
S3 URLs:
- Path-style: https://s3.region.amazonaws.com/bucket/key
- Virtual-hosted: https://bucket.s3.region.amazonaws.com/key

Additional Resources

DigitalCloud Training Cheat Sheets

AWS Storage Services Cheat Sheet - Comprehensive storage services reference for exam prep

Official AWS Documentation

Amazon S3 Documentation
Amazon EBS Documentation
Amazon EFS Documentation
S3 Storage Classes
AWS Skill Builder Storage Training - Free storage courses and certification prep
AWS Storage Learning Plans - Comprehensive storage learning paths
AWS Builder Labs - Hands-on storage labs and practice environments

AWS Storage Resources

S3 Pricing - Current storage pricing
EBS Pricing - Block storage pricing
EFS Pricing - File storage pricing
S3 Glacier Pricing - Archive storage pricing

Next: Database Services

Domain 3: Storage Services ​

Learning Objectives ​

Amazon S3 (Simple Storage Service) ​

Overview ​

Key Characteristics ​

S3 Core Concepts ​

1. Buckets ​

2. Objects ​

3. S3 Storage Classes ​

4. S3 Features ​

5. S3 Security ​

6. S3 Performance ​

Amazon EBS (Elastic Block Store) ​

Overview ​

Key Characteristics ​

EBS Volume Types ​

EBS Snapshots ​

EBS Encryption ​

Amazon EFS (Elastic File System) ​

Overview ​

Key Characteristics ​

EFS Performance ​

EFS vs EBS ​

EFS Storage Classes ​

S3 Security Deep Dive ​

Block Public Access ​

Encryption Options ​

Encryption in Transit ​

Exam Tips - Storage Services ​

High-Yield Topics ​

Additional Resources ​

DigitalCloud Training Cheat Sheets ​

Official AWS Documentation ​

AWS Storage Resources ​

Domain 3: Storage Services

Learning Objectives

Amazon S3 (Simple Storage Service)

Overview

Key Characteristics

S3 Core Concepts

1. Buckets

2. Objects

3. S3 Storage Classes

4. S3 Features

5. S3 Security

6. S3 Performance

Amazon EBS (Elastic Block Store)

Overview

Key Characteristics

EBS Volume Types

EBS Snapshots

EBS Encryption

Amazon EFS (Elastic File System)

Overview

Key Characteristics

EFS Performance

EFS vs EBS

EFS Storage Classes

S3 Security Deep Dive

Block Public Access

Encryption Options

Encryption in Transit

Exam Tips - Storage Services

High-Yield Topics

Additional Resources

DigitalCloud Training Cheat Sheets

Official AWS Documentation

AWS Storage Resources