Block Storage

What is block storage?

Block storage, also known as block-level storage, is a way to save data in chunks called blocks. Imagine a bookshelf where each book is split into separate pages and scattered around. Each page is like a data block with its unique label. Instead of placing these pages in order, they're stored wherever there's space.

The system quickly gathers all pages based on labels and arranges them when someone wants to read the book. This is how block storage works, making it fast and efficient. Storage area network (SAN) decides where to place data blocks to ensure better efficiency. It's used mainly in big computer networks and cloud systems because of its speed.

Data is spread across different computers, systems, or IT environments in block storage, making it easy to access the data from various places quickly. It's like having multiple paths to find those scattered pages. The team can edit the components within individual data blocks as needed. Many organizations use block storage software to edit separate data block components.

Benefits of block storage

Block storage is suitable for high performance and quick access to data. Below are some notable benefits that make it a preferred choice for IT teams. 

• High efficiency. Block storage offers high input/output operations per second (IOPS) and low latency, making it a top pick for high-demand applications.
• Compatibility. It’s versatile, working across diverse operating systems and file systems.
• Flexibility. Horizontal scaling is relatively simple. Teams can add cluster nodes when they need more storage.
• Enhanced performance. Block storage typically outperforms other storage forms. It minimizes latency, ensuring that applications work at their peak.
• Incremental changes. Teams can modify files without redoing everything. Replace, delete, or insert blocks as needed. It's perfect for files that get regular updates, like in databases.
• Reliability. If something goes wrong, restoring data is straightforward and quick.
• Limited metadata. Using unique block identifiers rather than extensive metadata means faster data retrieval with minimal overhead.
• Granular control. Developers can optimize data storage, grouping certain data types for improved performance. For instance, rapid-changing data might go on a solid state drive (SSD), while less-accessed data resides on a hard disk drive (HDD).

How block storage works

A block contains a specific amount of data. It usually ranges from 256KB to 4MB. Here’s how its storage and reading works.

• Data breakdown. Data gets divided into independent, fixed-size blocks, each acting as a separate storage piece. Entire files are spread across multiple, non-sequential blocks.
• Data lookup table design. Unlike typical storage, block storage doesn't track detailed metadata like file type and ownership. Instead, applications have custom data lookup tables to manage block data.
• Writing data. During storage, the system breaks data into block-sized chunks. Each chunk is written to a block, and its location is noted in the lookup table for reference.
• Reading data. To retrieve a file, the server consults the data lookup table, identifies the necessary blocks, and fetches them. The application then reconstructs the file from these blocks.

Block storage use cases

Block storage benefits make it suitable for applications that require high performance. Below are some typical applications of block storage in the industry.

• Containers. Block storage simplifies container management and migration by aiding container platforms like Kubernetes to offer persistent storage for the entire container.
• Email servers. Email platforms, especially Microsoft Exchange (which doesn’t support network-attached storage), benefit from block storage’s adaptability and scaling capabilities.
• Databases. Block storage shines with databases, particularly those with high query volumes. Its speed and efficiency ensure low latency and reliable data handling.
• Disaster recovery. As a backup solution, block storage ensures quick data restoration by facilitating rapid data movement from backup to active use. 
• Mission-critical applications. Block storage's high-speed performance guarantees consistent availability and reliability for essential apps like Oracle, SAP, and Microsoft SharePoint.

Block storage vs. object storage vs. file storage

Block, file, and object storage are three ways to save data, each with benefits and uses. 

Block storage splits data into small blocks and stores them separately, each with a unique label. It’s best for quick data access. Extensive computer networks and cloud systems use it more often. 

Object storage breaks data into objects, each with an identity document (ID) and detailed information (metadata) about the file. It’s best for large volumes of data, where custom details about each file are beneficial. Imagine a bookshelf where each book has a detailed summary attached.

File storage stores data in a traditional system of folders and files, similar to your computer's file explorer. It’s best for situations where a typical file structure is needed. It's like a bookshelf where each book is in its place. Network-attached storage (NAS) systems prefer using file storage. 

Businesses can choose the storage types depending on their needs like: 

• Quick data access? Go for block storage.
• Standard file system? Opt for file storage.
• Large-scale data storage? Select object storage.

Learn more about object storage and understand why it’s crucial for managing cloud data.