VMware VSAN features and realities
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With its Virtual SAN, VMware Inc. is no longer dancing around its role in storage. The hyper-converged software makes VMware just as much a storage company as the many vendors who sell nothing but storage.
VMware isn't hiding that fact either. CEO Pat Gelsinger made it clear during the VMware Virtual SAN (vSAN) online launch Thursday that storage is a critical piece of the company's strategy. He spoke of storage vendors such as EMC Corp. (VMware's parent company) and NetApp Inc. as partners, but VMware vSAN is clearly designed to compete with storage systems on the market.
VSAN pools hard drives and flash storage from a cluster of ESXi hosts to provide shared storage for virtual machines (VMs). Storage is provisioned and managed from the hypervisor. The product has been in beta for six months and will become generally available (GA) next week.
Unlike other VMware storage products, vSAN does more than add storage-related features to hypervisors or give small companies access to shared storage. VSAN is built for enterprise scale. Out of the gate, it supports 32 nodes (up from the eight nodes in beta and the 16 nodes VMware said it would support last month), 4.5 petabytes and 2 million IOPS. However, it lacks the storage and data management features it needs to be a true enterprise system. Early uses for vSAN will likely be storage for a virtual desktop infrastructure (VDI) and remote offices.
Like other VMware storage products, vSAN isn't designed for traditional storage administrators. Its target is server and application admins who want storage without setting up LUNs and RAID groups; the same target audience that hyper-converged and VM-aware storage startups go after.
Gelsinger said storage completes VMware's software-defined data center strategy, forming the fourth leg along with compute, server and networking.
"Why storage?" Gelsinger asked. "Why is VMware doing storage? We're the virtualization company. The answer is simple: Storing and managing data is one of the most critical functions that the data center -- it's called the data center -- is responsible for. It's also a major pain point and a major challenge for our customers today. Companies are fundamentally differentiating their company based on how they store, operate and analyze data."
VMware claims 12,000 customers signed up for its beta program. The vendor will make vSAN GA as a software download or on pre-configured hardware systems from partners. VMware lists Cisco, Dell, Fusion-io, HGST, Hewlett-Packard, IBM, Intel, LSI, Samsung Electronics, SanDisk and Seagate as hardware partners. Customers can also build their own VMware vSANs with any hardware that supports VMware hypervisors.
A vSAN cluster requires vCenter Server; at least three vSphere hosts with SAS or SATA host bus adapters or RAID controllers; at least one SAS or SATA hard disk drive; and one SAS, SATA or PCI Express flash device. Each host also needs a Gigabit Ethernet (GbE) or 10 GbE (recommended) network card.
Gelsinger said the value of vSAN is that it makes storage "radically simple, high-performance and cost-effective." We can't judge the last attribute yet, because VMware won't release pricing until vSAN goes GA next week. Performance will be judged by each user. We do know vSAN is missing valuable storage features, such as deduplication/compression; tiering; wide striping or erasure coding; advanced data protection, such as continuous data protection; and policy-based data movement to the cloud. In other words, it's software-defined storage without many of the features we associate with storage software.
VMware can add storage management features in future releases. Customers can also get them through third-party software products, but that reduces the cost-effectiveness and simplicity of vSAN.
It does appear easy to set up and manage, at least compared with traditional LUN-based storage. It's not as simple as the "two-click provisioning" that VMware claims because it takes more clicks to set up the storage policies, but that process is simple enough. VMware Chief Technology Officer Ben Fathi demonstrated a vSAN implementation during Thursday's launch, quickly setting storage policies for resiliency (number of failures to tolerate) and performance (number of disk stripes per object and the amount of flash read cache to reserve), and deploying an application by clicking through drop-down menus.
"I didn't have to worry about LUNs, RAID configurations, or any of that, or use any specialized management," Fathi said after the demo. "I think you will see storage in a whole new way going forward."
Fathi added that a 32-node vSAN can store 3,200 VMs. "This will take care of the storage requirements of pretty much any enterprise out there," he said.
How will vSAN affect the storage landscape?
VMware's vSAN launch included video testimonies from server vendors Cisco, Dell and IBM, plus EMC and Intel. The server vendors and Intel should be happy with vSAN because it adds value to their servers by turning them into shared storage. It bears watching how vSAN will eventually be received by EMC, which could lose storage array revenue if hyper-convergence takes off. For now, EMC will likely push its ViPR software-defined storage as a value-add to vSAN.
Smaller vendors may not welcome vSAN, which is seen as a threat to hyper-converged systems sold by Nutanix, SimpliVity and Maxta, as well as VM-aware storage from Tintri. VSAN can also hurt flash array vendors that have had early success selling storage for VDI.
Nutanix CEO Dheeraj Pandey, whose company is the most successful of the hyper-convergence startups so far, has a different take on vSAN. He said VMware can help Nutanix by shifting the acquisition and provisioning of storage to server and application admins. They are also the people Nutanix sells to.
"People try to draw a false equivalency between us," he said. "We're running server workloads and databases and mail servers and ERP applications on top of Nutanix. They will overlap at the VDI market, but I believe this empowers the VDI guys and the server guys, and will suck the wind out of the SAN companies. This is more trouble for the EMCs, NetApps and storage vendors because all of a sudden the decision-making authority will be with the application guys. That is exactly what a company like Nutanix needs from a large company like VMware, and we can ride on the coattails."