Task Statement 4.1: Design cost-optimized storage solutions.
📘AWS Certified Solutions Architect – (SAA-C03)
Overview
In AWS, storage is categorized into three main types:
- Object Storage
- File Storage
- Block Storage
Each type has unique characteristics, use cases, and AWS services. Understanding these differences is critical for designing cost-optimized storage solutions, which is a key exam topic.
1. Object Storage
Definition:
Object storage stores data as objects, not files or blocks. Each object contains the data itself, metadata (extra information about the object), and a unique identifier (key).
AWS Service Example:
- Amazon S3 (Simple Storage Service)
Characteristics:
| Characteristic | Description |
|---|---|
| Access | Accessed via APIs (like REST or SDKs). Not mounted as a drive. |
| Scalability | Virtually unlimited storage. |
| Durability | Extremely high (11 9s, 99.999999999% for S3 Standard). |
| Performance | Best for large numbers of files, not for transactional workloads. |
| Metadata | Custom metadata can be added to each object. |
| Cost Optimization | Supports multiple storage classes: S3 Standard, S3 Intelligent-Tiering, S3 Standard-IA (Infrequent Access), S3 Glacier (archival), S3 Glacier Deep Archive. |
Use Cases in IT Environments:
- Storing application logs from servers
- Backups of virtual machines (VMs)
- Large datasets for analytics (like CSVs or JSON files)
- Serving static content for websites (like images, CSS, JS files)
Key Exam Tip:
- Remember S3 is object storage → you cannot attach it directly to an EC2 instance as a drive.
- Different S3 storage classes exist to optimize costs based on access patterns.
2. File Storage
Definition:
File storage organizes data in a hierarchical structure (folders and files) and is accessed over a network.
AWS Service Examples:
- Amazon EFS (Elastic File System) – for Linux workloads
- Amazon FSx – for Windows (FSx for Windows File Server) or high-performance workloads (FSx for Lustre)
Characteristics:
| Characteristic | Description |
|---|---|
| Access | Mounted as a network drive using NFS (Linux) or SMB (Windows). |
| Shared Access | Multiple instances can read/write concurrently. |
| Scalability | Can scale up or down automatically (EFS is elastic). |
| Performance | Performance depends on throughput and IOPS; can be configured for high-performance workloads. |
| Durability | Stored across multiple Availability Zones for redundancy. |
| Cost Optimization | Pay for storage used; performance tiering may affect costs. |
Use Cases in IT Environments:
- Shared file systems for applications (e.g., storing application configs)
- Content management systems requiring shared access to files
- Home directories for Linux users on EC2
- High-performance computing (HPC) workloads with FSx for Lustre
Key Exam Tip:
- File storage is network-attached and can be shared between multiple servers.
- EFS → Linux & NFS; FSx → Windows & SMB.
- Know when to choose file storage vs. block storage.
3. Block Storage
Definition:
Block storage splits data into fixed-size blocks. These blocks can be stored and managed independently, like the storage in a hard disk or SSD. EC2 instances see block storage as a drive.
AWS Service Example:
- Amazon EBS (Elastic Block Store)
Characteristics:
| Characteristic | Description |
|---|---|
| Access | Attached to a single EC2 instance at a time (except with Multi-Attach). |
| Performance | High-performance options with SSD-backed (gp3, io2) or HDD-backed (st1, sc1). |
| Durability | Data is replicated within a single AZ. |
| Use Cases | Operating system drives, databases, or applications requiring low-latency I/O. |
| Cost Optimization | Choose volume type based on performance needs; delete volumes not in use. |
Use Cases in IT Environments:
- EC2 boot volumes (OS disks)
- Databases requiring fast read/write access (MySQL, PostgreSQL)
- Applications needing low-latency access to storage
Key Exam Tip:
- Block storage is like a virtual hard drive.
- Only one EC2 instance can attach a block volume at a time (unless Multi-Attach is used).
- SSD → better for transactional workloads, HDD → cheaper for throughput-heavy workloads.
Summary Table: AWS Storage Types
| Feature | Object Storage (S3) | File Storage (EFS/FSx) | Block Storage (EBS) |
|---|---|---|---|
| Access Method | API | Network mount (NFS/SMB) | Attached as drive |
| Scalability | Unlimited | Elastic | Limited to volume size |
| Shared Access | No | Yes, multi-instance | No (except Multi-Attach) |
| Performance | Depends on storage class | Configurable throughput | High IOPS / low latency |
| Durability | 11 9s (S3) | Multi-AZ replication | Single-AZ replication |
| Typical Use | Backups, static content, big data | Shared file systems | OS disks, databases, apps |
| Cost Optimization | Storage classes + lifecycle policies | Performance tiers | Choose volume type & delete unused |
Exam Tips for SAA-C03
- Know the access patterns: Object = API, File = Network share, Block = Attached drive.
- Choose storage type based on workload:
- Shared access → File
- Low-latency I/O → Block
- Large datasets/backups → Object
- Understand cost optimization options:
- Object → S3 storage classes, lifecycle rules
- File → EFS performance modes
- Block → EBS volume types, snapshots
