AWS S3 vs AWS EBS that finally makes sense with real world example
Got confused about S3 and EBS block storage and deciding the which service to use at which situation? Well, I got you!! Here is the simple difference on S3 and EBS with real world example that make you understand the the whole story and after reading this article you may also get knowledge about when to use service at what situation. At the end of the article i will be providing some quiz for knowledge check after reading this article.
Amazon S3 vs Amazon EBS: A Real-World Example That Finally Makes AWS Storage Easy to Understand
Introduction: Why Does AWS Have Two Different Storage Services?
When I started learning AWS, one question seemed confusing:
If Amazon S3 and Amazon EBS both store data, why do we need two different services?
Can't we simply choose one storage service and save everything there?
The answer becomes much easier to understand when we stop memorizing definitions and start thinking about how real applications work.
Imagine that you are building an online shopping application. Customers browse products, place orders, upload documents, and receive invoices. Behind the scenes, your application must store product images, customer information, order records, and other files.
Would you store all this information in the same way?
Probably not.
Some data needs to be accessed like files in an online warehouse. Other data needs to be read and updated quickly by an application running on a server.
This is the fundamental difference between Amazon S3 and Amazon EBS.
In this article, we will understand both services using a single real-world example, compare their differences, and learn when to choose each one.
1. First, Understand the Two Services
Before looking at our example, let's understand the basic idea behind each service.
Amazon S3: Think of It as a Digital Warehouse
Amazon S3 stands for Amazon Simple Storage Service.
It is an object storage service designed to store and retrieve data such as images, videos, documents, backups, and logs.
Think of S3 as a large digital warehouse.
You can put files into the warehouse, organize them using buckets and object keys, and retrieve them whenever an authorized application or user needs them.
For example, an online shopping application might store:
- Product photographs
- Product demonstration videos
- PDF invoices
- Customer-uploaded documents
- Application backups
- Historical reports
S3 stores each item as an object. An object includes the data, a key used to identify it, and associated metadata.
You generally access these objects through APIs, SDKs, or other supported interfaces rather than treating the bucket as an ordinary hard drive.
Remember: Amazon S3 = Store and retrieve objects.
Amazon EBS: Think of It as a Hard Drive Attached to a Computer
Amazon EBS stands for Amazon Elastic Block Store.
It provides block storage volumes primarily for Amazon EC2 instances.
Imagine that you purchase a computer. The computer needs a hard drive to store its operating system, installed applications, and data that those applications frequently read and update.
EBS serves a similar purpose for an EC2 virtual server.
For example, an EC2 instance running an online shopping application might use an EBS volume for:
- Its operating system
- Application files
- Local working files
- Database files when a database is hosted on that instance
- Other data requiring block-level storage
The operating system can format the EBS volume with a filesystem and use it much like a disk.
An EBS volume persists independently of the lifecycle of its associated EC2 instance, subject to its configuration and deletion settings.
Remember: Amazon EBS = A virtual hard drive for your EC2 server.
2. The Real-World Example: Building an Online Shopping Website
Let's imagine that we are building an online shopping website called ShopSmart.
Customers can browse products, add items to their cart, place orders, and download their invoices.
Our application has three main requirements:
- It must run on a server.
- It must store and update order information.
- It must store thousands of product images and downloadable documents.
Now let's decide where each type of data belongs.
Requirement A: Running the Application
Our website needs a server to execute its application code.
We launch an Amazon EC2 instance and install the required operating system and application software.
Where does the operating system need to store its files?
It needs disk storage.
This is where Amazon EBS comes in.
We attach an EBS volume to the EC2 instance and use it as the server's disk.
When the server starts, the operating system and application can access the files stored on that volume.
Our choice: Amazon EBS.
Why? Because the server needs block storage that its operating system can use as a disk.
Requirement B: Storing Order Information
Suppose a customer purchases two shirts.
The application needs to record details such as:
- Order ID
- Customer ID
- Product ID
- Quantity
- Total amount
- Order status
If we run a database such as MySQL directly on our EC2 instance, its database files could be stored on EBS.
The database can then read and update those files using normal database operations.
However, there is an important distinction: EBS is storage, not a database service. If we use Amazon RDS instead, AWS manages the database infrastructure, and the underlying storage is handled by the database service.
For this example, assume that we are running MySQL on our own EC2 instance.
Our choice: Amazon EBS for the database's disk storage.
Why? The database needs storage suitable for frequent reads, writes, and updates.
Requirement C: Storing Product Images
Now imagine that ShopSmart has 20,000 products.
Each product may have several images. The application must store, retrieve, and serve these images to customers.
Should we save every image on the server's EBS volume?
We could, but it may be more convenient to keep product images in storage designed for scalable object access.
This is where Amazon S3 becomes useful.
We create an S3 bucket and upload the images as objects. The application can store the corresponding object keys in its database and retrieve the images when required.
For example:
- S3 object key:
products/shirt-101/front.jpg - Database record: Product ID
101 - Image reference:
products/shirt-101/front.jpg
The database holds the product information and image reference, while S3 stores the actual image.
Our choice: Amazon S3.
Why? Product images are objects that the application needs to store and retrieve independently of the server's disk.
Requirement D: Storing PDF Invoices
After a customer completes an order, the application generates a PDF invoice.
Where should we store it?
If the invoice is a file that must be retained and downloaded later, S3 can be a suitable option.
The application uploads the PDF to S3 and records the invoice reference in the database.
For example:
invoices/ORD-10025.pdfWhen the customer wants to download the invoice, the application checks authorization and provides access to the stored document.
The object should not be publicly accessible merely because it needs to be downloadable. Access can be controlled through IAM permissions, bucket policies, and appropriately configured temporary URLs.
Our choice: Amazon S3.
Why? A PDF invoice is a file-like object that can be retrieved when needed.
3. Let's Visualize the Complete Application
Here is how the two services can work together.
Customer → ShopSmart application running on EC2 → EBS for the server's disk and database files, where applicable; S3 for product images and PDF invoices.
The application connects the two storage services according to the type of data it needs.
For example, when a customer opens a product page:
- The application retrieves the product details from its database.
- The database returns the image reference.
- The application retrieves the corresponding image from S3.
- The website displays the product to the customer.
When a customer places an order:
- The application validates the order.
- The database records the order information.
- The application generates an invoice.
- The invoice is uploaded to S3 if that is the chosen document-storage design.
- The database stores the invoice reference.
This architecture illustrates an important lesson: S3 and EBS are not competitors that must always replace one another. They can solve different storage problems in the same application.
4. Amazon S3 vs Amazon EBS: The Important Differences
| Feature | Amazon S3 | Amazon EBS |
|---|---|---|
| Storage type | Object storage | Block storage |
| Simple analogy | Digital warehouse | Virtual hard drive |
| Typical access | APIs and object operations | Disk and filesystem operations |
| Common use cases | Images, documents, backups, logs | Operating systems, databases, application disks |
| Relationship with EC2 | Accessed by applications through supported interfaces | Volumes attach to EC2 instances |
| Capacity management | Designed to scale to very large amounts of object data | You create and manage volumes with configured capacity |
| Data organization | Buckets and object keys | Blocks, partitions, filesystems, and files |
| Backup options | Versioning, replication options, and other data-protection features | Point-in-time snapshots and other backup options |
Both services offer security and data-protection features, but their configurations, performance characteristics, availability considerations, and pricing models differ.
S3 costs depend on factors such as storage class, data stored, requests, retrieval, and data transfer. EBS costs depend on factors such as volume type, provisioned capacity, performance configuration, and snapshots.
Always evaluate the current AWS pricing for your specific workload before deciding which option is cheaper.
5. Can We Store Everything in S3 Instead of EBS?
This is a common question.
If S3 can store images, documents, and backups, why not store the operating system and database files there too?
The reason is that the two services expose data differently.
An operating system expects its disk to support block-level operations. A database running on a server also expects storage behavior compatible with its requirements.
S3 is object storage accessed through APIs. It does not behave like a normal block device attached to the operating system.
You cannot simply point an ordinary EC2 boot volume or database data directory at a standard S3 bucket and expect it to work as a normal hard drive.
Specialized tools can expose object storage through different interfaces, but those approaches do not make S3 identical to EBS. Compatibility and performance must be evaluated for the specific application.
Similarly, EBS is not automatically the best place for every image, document, and backup simply because the application server already has an attached disk.
Choose the storage service according to how the application needs to access the data.
6. What About Backups? Can S3 and EBS Work Together?
Yes!
Imagine that ShopSmart's MySQL database is stored on an EBS volume.
The team wants to protect its data in case the volume needs to be restored.
EBS supports snapshots, which provide point-in-time backups of EBS volumes. AWS manages the underlying snapshot storage, and users can restore a volume from a snapshot when needed.
The team can also create logical database backups and upload those backup files to S3.
For example:
- EBS volume: The database's active disk storage.
- EBS snapshot: A point-in-time volume backup.
- S3 object: A logical database backup file uploaded by the application or backup process.
These are different backup approaches. A logical database backup is not the same thing as an EBS snapshot, and each has different recovery characteristics.
A good backup strategy should also consider retention, access permissions, recovery testing, and protection against accidental deletion.
7. A Simple Decision Guide
When deciding between S3 and EBS, ask yourself these questions.
Question 1: Does the operating system need to use this storage like a disk?
Choose EBS when you need block storage for an EC2 instance.
Question 2: Am I storing files such as images, videos, documents, or backups for retrieval through an application?
S3 is often a good fit.
Question 3: Does my database need disk storage for frequent reads and writes?
EBS can be appropriate when the database runs on EC2 and requires block storage. A managed database such as Amazon RDS may be a better operational choice for other requirements.
Question 4: Do I need to store a large collection of files separately from my application server?
S3 is worth considering.
Question 5: Do I need both?
Very often, yes. Many applications use EBS for server disks and S3 for objects, documents, and backups.
The right answer depends on the workload, not simply on which service sounds more powerful.
8. Test Your Understanding
Let's see whether the difference is clear now.
Imagine that you are building a college portal.
Where would you store each of the following?
- The operating system of an EC2 instance.
- Student profile photographs.
- Database files for MySQL running directly on EC2.
- PDF notes uploaded by students.
- Backup files exported by a database backup process.
Suggested answers:
- EBS
- S3
- EBS
- S3
- S3 can be suitable for the exported backup files.
These are typical choices, not universal rules. A different architecture or managed service may change the design.
Conclusion: Remember One Simple Difference
You do not need to memorize every AWS storage feature to understand the basic distinction.
Think about the online shopping application again.
The application server needs a disk to run its operating system and, in our example, store its database files. Amazon EBS provides that block storage.
The application also needs a place to store product images, PDF invoices, and other objects. Amazon S3 provides scalable object storage for those files.
The simplest way to remember the difference is:
Amazon EBS = A hard drive for your server.
Amazon S3 = A digital warehouse for your objects.
Neither service is universally better. They solve different problems, and understanding those problems is the first step toward designing a good cloud architecture.
Let's Discuss!
Now I have three questions for the AWS community:
- If you were building a photo-sharing application, would you store uploaded images on EBS or S3? Why?
- For a production application, would you run MySQL on EC2 with EBS or choose Amazon RDS?
- What is the most confusing AWS storage concept you encountered when you first started learning cloud computing?
Share your answers and reasoning in the comments. I'd love to learn how other developers approach these decisions.
Enjoyed reading this content? Let the author know!
Your likes, comments, shares, and saves help creators reach more builders.
Loading recommendations
Loading article