Storage Virtualization: Pooling Storage Resources For Flexibility

Storage virtualization has delivered massive benefits to data center operators and their clients/users. Here is a quick guide to what you need to know about it.

Understanding storage virtualization

Storage virtualization abstracts physical storage resources into a unified, manageable pool, enabling seamless access and management across various storage devices. This abstraction layer decouples storage from the hardware, allowing for more flexible and efficient use of storage resources within data center environments.

Core concepts of storage virtualization

There are five core concepts that underpin storage virtualization. Here is an overview of them.

Abstraction

Abstraction refers to separating the logical storage from the physical hardware. This principle allows administrators to manage storage resources without needing to interact directly with the underlying hardware. Logical volumes can be created, resized, and allocated dynamically, providing a more flexible and responsive storage environment.

Pooling

Pooling refers to aggregating storage resources from multiple physical devices into a single, unified storage pool. This collective pool can then be divided and allocated as needed, optimizing resource utilization. By pooling storage, data centers can improve efficiency and flexibility, enabling better allocation of storage based on demand and reducing wasted capacity.

Automation

Automation involves using software to manage storage tasks such as provisioning, backup, replication, and migration. Automated processes reduce manual intervention, decreasing the likelihood of human error and improving operational efficiency. This principle ensures that storage resources are used optimally and can adapt quickly to changing demands, enhancing overall data management.

Scalability

Scalability is the ability to expand storage resources seamlessly as demand grows. Storage virtualization allows for easy integration of additional storage devices into the existing pool without disrupting operations. This capability ensures that data centers can scale their storage infrastructure in a cost-effective and efficient manner, supporting growing data volumes and increasing performance requirements.

Centralized management

Centralized management provides a single interface to oversee the entire storage environment, regardless of the physical location of the storage devices. This principle simplifies administrative tasks, enabling better monitoring, reporting, and control. Through centralized management, storage administrators can manage resources more effectively, ensuring data availability and performance.

Types of storage virtualization

There are five main types of storage virtualization in mainstream use. Here is an overview of them.

Block storage virtualization

Block storage virtualization abstracts the logical storage blocks from the physical storage devices. This type of virtualization treats storage as a series of uniformly sized blocks, which can be managed and allocated independently of the physical storage hardware.

It enables the creation of virtual disks, which can be dynamically resized and allocated to different applications as needed.

Block storage virtualization is typically implemented at the SAN (Storage Area Network) level, allowing for high performance and low latency access to storage resources, making it ideal for applications requiring fast I/O operations.

File storage virtualization

File storage virtualization abstracts file-level data from the physical storage devices, presenting a unified file system to users and applications. It aggregates multiple file servers and storage systems into a single, cohesive file system namespace.

This approach simplifies data access and management by allowing users to access files without needing to know the specific location of the data.

It is commonly used in NAS (Network Attached Storage) environments, providing a flexible and scalable solution for managing large volumes of file-based data, such as documents, images, and videos.

Object storage virtualization

Object storage virtualization abstracts data into objects, which consist of the data itself, metadata, and a unique identifier.

Unlike block or file storage, object storage does not use a hierarchical structure. Instead, it stores data in a flat address space, enabling easy scalability and efficient management of large amounts of unstructured data.

Object storage virtualization is often used in cloud storage environments and is suitable for applications requiring high scalability and durability, such as backup and archival systems, content distribution, and big data analytics.

Host-based storage virtualization

Host-based storage virtualization is implemented at the server level, where the virtualization software resides on the host machine.

This approach allows the host to manage and control storage resources directly, abstracting the physical storage into virtual volumes that the operating system and applications can use. It provides flexibility and ease of use, as it can be implemented without requiring changes to the existing storage infrastructure.

Host-based storage virtualization is ideal for environments with limited storage resources and is often used in conjunction with other virtualization technologies, such as server virtualization.

Network-based storage virtualization

Network-based storage virtualization is implemented within the storage network, typically using dedicated appliances or switches that reside between the servers and storage devices. These devices create a virtualized storage layer that aggregates and manages the physical storage resources across the network.

This approach offers high levels of flexibility and performance, enabling dynamic allocation of storage resources and centralized management. It is commonly used in large-scale enterprise environments where managing and optimizing storage resources across a wide range of devices and locations is critical.