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Virtualization has enabled businesses to manage server resources more easily. Recently, corporations have been...
adding such features to their storage systems. VMware VSAN 6.2 has emerged as a leader in this space and is also gaining traction as a hyper-converged offering, but the product does present customers with a few challenges.
Interest in software-defined storage (SDS) is growing for a variety of reasons, starting with rising storage volumes. The digital universe is expected to double in size every two years between now and 2020, when it reaches 44 zettabytes of information, according to IDC.
In this ever expanding storage universe, deploying traditional offerings such storage area networks and network attached storage can be time-consuming and cumbersome.
"As storage grows, companies have trouble scaling up," said Eric Burgener, research director for IDC's Storage Practice.
Often moving from a small system to a large one requires a complete switch of the underlying hardware.
Virtualizing storage systems and dealing with bottlenecks
VMware VSAN is an object-based storage system that aims to simplify VM storage configurations for VMware administrators. The product was designed to leverage VMware's traditional strength: virtualization. Unlike other SDS options, VSAN operates at the hypervisor level rather than at the operating system or the storage system level.
VSAN 6.2 aggregates a server-attached disk into a single pool of storage. One benefit is businesses can scale their storage more easily. VSAN data store is built to increase capacity on the fly, so you can quickly add additional storage to hosts.
Another recent problem is storage systems have become system bottlenecks. Latency issues increase as offerings become denser and information moves among VMs, servers and storage systems.
VSAN 6.2 enables companies to more easily deploy multi-tiered storage. A company can remove apps with high performance requirements and place them on dedicated storage, perhaps even a flash array, which offers top end performance. VMware SDS -- another speed enhancement -- writes requests sequentially rather than randomly. Meanwhile, lower costs are another potential benefit.
"SAN and NAS hardware has been expensive because it has consisted largely of proprietary hardware," Burgener said. With VSAN 6.2, adding storage is a lot cheaper because the product operates on commodity hardware.
VSAN 6.2 has chameleon-like capabilities and can be positioned among hyper-converged systems from vendors like Nutanix and SimpliVity. These products bundle server, storage, network and hypervisor functions into a single product.
These systems are garnering significant interest. In fact, Technology Business Research projects that sales will increase at 50% Compound Annual Growth Rate from 2015 and reach the $7 billion mark in 2020.
VMware has positioned VSAN 6.2 in this market. The company's hyper-converged software stack works with vSphere and vCenter Server, so corporations deploy turnkey data center offerings.
VSAN 6.2 has early market issues
Even though it offers many potential benefits, opting for VSAN 6.2 creates challenges for businesses.
"SDS management tools are in a nascent stage," said George Crump, president of Storage Switzerland. While improving, they do not offer the visibility and flexibility found with more mature offerings.
Increased density is a double-edged sword. These offerings fit in smaller form factors that decrease real estate costs, but the growing data transmission volumes can overwhelm storage systems. Companies can move to all-flash arrays, but this approach can be expensive and may not work well with some applications.
The VMware hyper-converged option is software-based. Alternatives bundle the hardware and software in turnkey offerings. If a company operates a multi-hypervisor environment, problems arise.
"The VMware system does not work with other hypervisors," said Scott Sinclair, senior analyst at Enterprise Strategy Group.
In the end, companies need to make difficult decisions about the openness of their products.
"All of the hyper-converged products lock customers in some way," Crump said. The question becomes "Do customers want proprietary hardware or hypervisors?"
A variety of SDS offerings have emerged in response to the pressure of growing storage demands on IT departments. VMware VSAN 6.2 is gaining traction in the SDS and hyper-converged spaces, although the product may not fit neatly in every potential use case.
How is VSAN changing the storage game?