Within the enterprise data center, and in the cloud, block storage is a common solution to storing data efficiently and to maximize versatility.
Block storage devices assign volumes of storage which are then accessible for use by virtually any operating system. Volumes can be created with file systems that appear to the OS as independent drives, making them available for network file storage, Windows, VMware, and more.
What is Block Storage?
Block storage, compared to file storage or object technology, provides high performance and stores data efficiently in “blocks”. As opposed to object storage, block storage does not contain metadata, but simply a block address for use in retrieval of the data.
Since applications are responsible for storing and retrieving the data, there is minimal overhead from block storage devices in managing individual blocks of data, further enhancing its performance advantage.
Most storage area network (SAN) devices utilize block storage to benefit from the flexibility of placing any file system on the volumes, maximizing the use of the available space.
An additional benefit of block storage is that since different operating systems and file systems can be allocated to individual blocks, it’s possible to actually reboot systems on one block without impacting activity on another. This can be desirable in large organizations or within service providers.
What Makes Block Storage a Good Choice?
From a sheer flexibility and performance standpoint, block storage outshines alternative storage methods such as file storage or object storage, for several reasons:
- Since volumes can be defined with your choice of OS, the same block storage device can house varying types of data, managed by the associated OS or even third-party software for managing content.
- Transactional applications that utilize databases and require consistent high performance and a high volume of transactions are excellent candidates for block storage.
- Another key use of block storage is Microsoft’s own Exchange email system, which takes advantage of the inherent performance and flexibility of block data architecture.
- Virtual storage systems such as VMware also adopt block storage as their storage architecture, due to the ability to house multiple operating systems and data types within various file systems.
- Block level storage also has an advantage in that it can be configured to manage performance and storage capacity. This provides tools for administrators to monitor performance and make adjustments as needs change.
The downside – these management activities are necessary and important to maximize performance and make the best use of the available capacity of block storage.
Issues with Using Block Level Storage
Although block storage techniques have been in use for decades, there are caveats to be considered with this structure:
- When block level storage was introduced, applications and data typically resided on the same storage device, or at least were geographically colocated, as in the same data center. With the advent of the global enterprise, the internet of things (IoT), and mobile applications, this may no longer be the case. Since applications may reside on a tablet in Europe, with the data churning on a server in New York or some remote location, there can be a dramatic effect on performance.
This characteristic of block storage has been addressed by some cloud providers through storing multiple instances of data on servers in different geographic locations. Applications can then retrieve information from the location closest to them, improving performance.
- Block storage devices can be more expensive to acquire, and have incremental management and configuration costs associated with maintaining them.
- Having no metadata associated with block level storage limits the interaction or relationship with security functions that are supported with object storage methods.
Cloud Block Storage
Migration to the cloud is rapidly gaining popularity as small and midsize businesses become more reliant on IT services, and as enterprises leverage service providers to maximize their IT investment and expand globally.
Turning to service providers will invariably include adoption of block storage architecture, as most key players in cloud services utilize block storage functionality for its many advantages in the cloud:
- Ease of expansion – mounting a new ‘drive’ can increase storage capacity independently of adding computing power or servers – an advantage for both the provider and client
- Flexibility – different types of media are supported – traditional drives or flash storage
- Transportability – drives may be moved from one server to another, transparent to the applications
Who Uses Cloud Block Storage?
Leaders in cloud computing leverage block storage architecture for its flexibility and performance characteristics:
- Amazon Web Services (AWS)
- Dell /EMC
- Rackspace Cloud Block Storage
- Your business or enterprise?
By adopting block storage technology, these providers can offer services at attractive pricing based on a “pay for what you use” structure that is easily extended as clients’ needs grow.
As enterprises migrate more business-critical applications to the cloud, the attributes and expandability of block storage will certainly increase in popularity.