It is tempting for IT professionals to take a macro-view of hyper-converged infrastructure (HCI) and let the vendor take care of all the details. The problem is the details matter, especially in HCI. The key HCI components for IT to understand are; the hypervisor, storage software, hardware server nodes and networking software. Each component of HCI can make a big difference in performance, scalability and price of the solution.
The dominant hypervisor in the market is obviously VMware vSphere and most HCI solutions leverage it as the core of their solution. VMware also provides original equipment manufacturers (OEM) hyper-converged appliances based on vSphere and VMware’s Virtual SAN (VSAN) called VxRail. Almost every server hardware manufacturer offers a VxRail solution, even vendors that have their own porting solution.
Microsoft Windows Server Software-Defined (WSSD) is the most variable competitor to VMware in the enterprise. Most organizations find that WSSD is significantly less expensive than VMware. WSSD is software-only and enables customers to use their choice of server hardware as nodes. WSSD has important capabilities like a relatively easy on-ramp to the Azure cloud, making it easy for organizations to create a hybrid infrastructure. WSSD uses Storage Spaces Direct and delivers excellent storage IO performance (assuming the underlying server hardware can deliver it). We’ll detail Storage Space Direct in the next blog in this series.
Another dominant set of hypervisors are those based on Linux, most typically based in some fashion on KVM. Options include Red Hat Virtualization, which is used in Red Hat Hyperconverged, Nutanix Acropolis which dramatically simplifies the HCI experience and Scale Computing which also simplified KVM to make it appeal to mid-market customers.
Why the Hypervisor Matters
The hypervisor is a foundational component of the HCI solution. It is the “glue” that holds the other parts together. The hypervisor also, in the case of VMware, is an expensive part of that solution and is why the market has seen so many vendors embrace Microsoft WSSD or one of the KVM variants. The capabilities of the hypervisor can impact the HCI solutions’ ability to scale and its ability to support other technology initiatives like cloud storage and computing.
The reality is, while it hasn’t reached feature parity, the hypervisor market is reaching maturity and the differences between the various options are shrinking to the point that the hypervisor may no longer be the most important aspect of the solution. Organizations are also looking to be less tied to VMware, so solutions like Microsoft’s WSSD and the simplified KVM solutions are gaining in popularity.
An area of true separation is the storage software component of HCI. The storage software is sometimes delivered as part of the hypervisor like VMware’s vSAN and Microsoft’s Storage Spaces Direct, or as a stand-alone software solution that IT can add to an existing hypervisor. Our next blog discusses the various ways that storage software is delivered and the pros and cons of each method.
In the meantime check out our on demand webinar, “How to Put an End to Hyper-Converged Silos.” As part of the webinar you’ll also get an exclusive copy of our eBook “What is HCI 2.0”.