Server and storage virtualization have both been used for years, though virtualizing servers is the more popular trend.
Server virtualization got such a jump on storage virtualization that it's sometimes easy to overlook the drastic benefits virtualized storage can deliver in terms of storage efficiency and performance. According to Jon Toigo, CEO and managing principal of Toigo Partners International, and chairman of the Data Management Institute, storage virtualization is easier to implement than server virtualization and, in some cases is a better option than flash to fix the I/O bottlenecks created by server virtualization. In this guide, you'll get Toigo's expert advice on server and storage virtualization with answers to questions regarding common misconceptions about virtualization, what to look for when virtualizing an environment and developments in today's storage and hypervisors.
Table of contents:
IT pros carrying out server virtualization projects often don't consider what effects the process will have on their storage. According to Jon Toigo, server virtualization significantly alters I/O patterns, which can make implementation more difficult than people might expect. This expert answer outlines what people should look out for when virtualizing their servers and the best way to go about virtualizing an environment.
When servers are virtualized, the virtualization layer sends and receives I/O processes, rather than the controller that was handling the work previously. Because this virtualization layer stands between applications and physical hardware, it causes bottlenecks. Some users turn to flash and solid-state drives to remedy the slow performance. But, according to Toigo, using faster storage only masks the underlying problem.
While flash storage can improve performance, it comes with a high price tag. Toigo says the same outcome can be achieved by virtualizing storage. In this expert answer, you'll find a comparison of storage virtualization and flash technology, and how they each improve performance.
Two years ago, VMware Inc. attempted to solve the I/O bottleneck problem virtualization causes by developing a set of SCSI primitives that would improve performance by reducing workloads. The firm's vStorage APIs for Array Integration (VAAI) offloads processes to storage controllers -- but it will only work if the storage supports VAAI. In this answer, Toigo explains why he thinks many developments to storage are not made to improve functionality with virtualization, but rather to keep up with changes being made to hypervisors.