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Channel partners selling storage into virtualized infrastructure environments have a range of options, whether they focus on storage as their core business or as a follow-on sales opportunity.
There have been a lot of developments in this space in recent years, as established storage standbys evolve and new technologies enter the mix. For instance, storage-area networks (SANs), long the gold standard for storage infrastructure for server virtualization, now feature flash-based solid-state drives (SSDs). Channel companies can also explore emerging approaches such as converged infrastructure appliances. And direct-attached storage (DAS), which only a few years ago was deemed ill-equipped to support virtualized server or virtual desktop infrastructure (VDI) deployments, has resurfaced as a viable option as software-defined storage matures.
The upshot for resellers, integrators and other purveyors of storage: companies now have the ability to pick a storage product that addresses the specific virtualization needs of their customers. And those needs tend to be highly varied, which makes the ability to craft a flexible and responsive storage offering all the more critical.
Prior to virtualization, storage requirements were much more straightforward, noted Kent Christensen, practice director, virtualization and cloud at Datalink Corp., a data center services and solutions provider based in Eden Prairie, Minn. That story has changed with the rise of virtualization, however.
"When you talk about virtualization, the workload becomes less predictable," Christensen said. "In high-density virtualization or VDI, you just have an extreme amount of I/O (input/output) and a lot of random I/O."
Storage for the unpredictable
The multiple workloads running together on virtualized servers accomplish different tasks and experience different ebbs and flows in terms of demand. Accordingly, those workloads may have vastly different resource consumption profiles. Under such circumstances, the storage infrastructure faces unpredictable spikes in demand for I/O operations per second (IOPS).
The so-called blender effect further complicates the storage picture: multiple virtual machines (VMs) will mix their I/O streams together, resulting in random I/O processes. This randomization increases read/write activity, which drives up latency.
Virtualization, as it matures, pushes the limits of conventional SAN storage.
"As the density of virtual server, desktop and application infrastructure grows, traditional SAN storage becomes more challenged to deliver the performance required to combat the I/O blender effect that virtualization creates," said Bryan Rosenblum, director of solutions and services with Zones Inc.'s Advanced Solutions Group. Zones is an IT solutions provider based in Auburn, Wash.
The answer for many customers is flash technology, which offers greater performance than traditional spinning disk storage.
"For organizations with heavily virtualized environments, we see a clear need to define and execute a flash storage strategy," Rosenblum said.
He said Zones typically assesses a customer's infrastructure upfront, quantifies performance bottlenecks and then works with the customer to re-architect its storage environment to optimize the use of flash. Recommendations, he added, could include the following options:
- Server flash. Rosenblum said this technology, the highest-performing and most expensive form of flash to implement, may be considered for applications such as enterprise resource planning systems and highly transactional databases that routinely experience performance issues attributed to latency.
- All-flash arrays. Rosenblum said this approach makes sense for customers with large, multi-node database clusters and those looking to scale VDI deployments to thousands of users.
- Hybrid-flash platforms. These products, according to Rosenblum, are often recommended for general, multi-purpose workloads that include server virtualization.
Hybrid-flash SANs have become particularly popular among customers. In one example, Zones sourced a StorTrends 3500i SSD hybrid SAN array for Thomas, Judy Tucker (TJ&T), an accounting firm based in Raleigh, N.C. Drew Green, director of IT at TJ&T, said the company had been using DAS, but encountered capacity and performance limitations using that technology in its virtualized infrastructure environment.
"We had a wide range of different types of spinning disks, and none of it was consolidated into a centralized store repository," Green said.
"Hybrid storage arrays typically provide the best combination of price and performance," Rosenblum explained. "We have found the hybrid array approach to be a great fit for organizations looking to consolidate storage infrastructure, combining VMs, bare-metal servers and unstructured file data into a single array."
Stanton Girod, solutions architect at AR Consultant Group Inc., a Loganville, Ga.-based storage solutions provider, said nearly all of his customers want hybrid-flash arrays. He said hybrid technology has placed high-IOPS storage products within the budget reach of smaller companies.
"The price has come down enough," he said. "It is very affordable."
He called $50,000 "a good starting point" for hybrid array pricing.
The lower price point stems from a couple of factors. First, hybridization strikes a balance in which the faster but more expensive flash SSDs may be reserved for frequently accessed data, while spinning disks offer a cheaper tier of capacity for cooler data. Second, hybrid products offer deduplication and compression, which industry executives said can provide a data reduction ratio of 5:1 or better. Customers can purchase fewer flash SSDs -- and save money -- if they have less data to store.
At Datalink, Christensen said deduplication and compression combine to make hybrid flash technology economical for "sweet spot" applications such as high-performance databases and virtualization. Datalink partners with hybrid-flash vendors such as Nimble Storage.
In addition to Nimble, vendors that provide hybrid-flash arrays and appliances include American Megatrends Inc.'s StorTrends division, EMC, HP, NetApp, Tegile Inc. and Tintri. Vendors that focus on all-flash products include Pure Storage Inc. and Nimbus Data Systems Inc.
Converged infrastructure appliances
Storage solution providers may also leverage converged infrastructure appliances to support their customers' virtualization needs. Vendors, including HP, Nutanix, Scale Computing and SimpliVity Corp., combine compute, storage and network switching components within a single appliance. Converged infrastructure providers target server virtualization and VDI deployments.
Bryan Rosenblumdirector of solutions and services, Advanced Solutions Group, Zones Inc.
Converged platforms "simplify virtualization environments by reducing the amount of switching needed and improve management," said Joe Brown, president of Accelera Solutions, a Fairfax, Va.-based service provider with a specialty in virtualization. "Additionally, they tend to minimize the amount of datacenter floor space required to run the environment."
Girod said AR Consultant Group works with Scale Computing in the converged infrastructure product category. He said converged products may get to the point where they cover 70% of the market, but added that some customers have storage demands beyond what a converged infrastructure appliance can satisfy.
That observation isn't a dig against converged storage, Girod said, noting that converged platforms aim for the middle of the bell curve. For customers on the more demanding side of that curve, AR Consultant Group may place a StorTrends array behind a converged infrastructure appliance, according to Girod.
Storage solutions providers can expect to see melding among the storage categories. For example, Nimble has been partnering with Cisco Systems Inc. and other vendors to provide its SmartStack converged infrastructure offering. SmartStack, according to Nimble, consists of Nimble flash storage arrays and Cisco UCS servers and network infrastructure.
Storage virtualization, sometimes referred to as software-defined storage, offers another possibility for channel partners selling storage into heavily virtualized accounts. One example: VMware's Virtual SAN (VSAN) technology, which provides software-defined storage for the company's vSphere server virtualization platform. VSAN pools server-attached storage into a shared data resource for virtual machines. The technology supports both hybrid and all-flash storage.
VSAN -- and technologies like it -- lets organizations preserve DAS and avoid the expense of a storage makeover.
"Customers can use VSAN to get more efficiency and cost savings from their direct-attached storage," Brown said.
Brown described virtual storage as a viable strategy for those organizations with the appropriate types of servers. He cited the following minimum requirements for direct-attached drives in servers:
- Drives should be at least 7200 RPM to avoid poor performance.
- Drives should be at least 100 GB in size to be useful in a virtual SAN setting. Smaller drives may be used, but they should be aggregated with 10 or more like drives.
- Drives should be SAS or Serial ATA format.
Rosenblum also noted VSAN's potential. But he expressed some reservations.
"VSAN makes it more viable for organizations to provision and manage direct-attached storage in the same manner you would from an array," Rosenblum said. "The question for VSAN is one of scalability. For mid-market and smaller companies, VSAN software technologies can be a viable approach and are clearly the most cost-effective option. For larger enterprise organizations, it can be cumbersome to perform maintenance across the internal hard drives of hundreds of servers as opposed to a single array."
Other players in the software-defined storage space include Nexenta Systems Inc. and Scality.
In addition to addressing general storage needs, virtual storage is finding a home in niche markets.
CineSys-Oceana, a company that builds workflow and storage offerings for the media and entertainment industry, works with Scality, which is carving out a role in this market. Brent Angle, chief technology officer at CineSys, said the company's customers, which include broadcasters and post-production facilities, all employ high-performance SANs as tier-one storage for supporting such tasks as ingesting, manipulating and editing video. But the company, which has headquarters in Houston and New York, is deploying Scality alongside tier-one storage for companies seeking a cost-effective way to speed up access to their video archives. Moving a video archive from tape to Scality's software-defined storage, which supports SSDs and traditional disks, permits faster access when a broadcaster's customers request footage.
It's a virtualization strategy that not only keeps costs in check, but could also generate revenue. A film archive that affords speedier access can be monetized, Angle noted.
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