Hyper converged infrastructure (HCI) has become viral in the IT realm. It has been described with adjectives such as miraculous and revolutionary. Vendors and analysts alike can’t stop singing the praises of the Total Cost of Ownership (TCO) benefits of HCI.
However, there is a hidden cost to HCI that none of its most avid supporters and evangelists ever talk about: Software Licensing. Before you embark on a hyperconverged infrastructure strategy, best to take heed with the advice you’re about to read. Your job, and possibly the success of your organization, could depend on it!
A Good Use Case for HCI – Virtual Desktop Infrastructure (VDI)
For a hyperconverged infrastructure to deliver the convenience and functionality promised, the nodes must be completely balanced—they cannot be storage or compute heavy. Henceforth, balance becomes increasingly difficult.
VDI is the epitome of a balanced workload:
- You typically have a common desktop image build (i.e. Windows 10) with standard vDisk, vCPU and vRAM allocations
- The two leading VDI solutions on the market, Citrix XenDesktop and VMware Horizon View, both license their products on a per user basis and include rights to their respective HyperVisor technology with the per user entitlement
- There is a minimal risk of data loss since Desktop VMs can be quickly regenerated in the event that there is an HCI storage corruption that causes data loss.
The above characteristics make HCI a good choice for VDI from a TCO perspective.
Why HCI is not a Fit for Mission Critical Microsoft SQL Server or Oracle DB Server Workloads
Hyper converged infrastructure combines compute and storage resources into units called HCI Nodes. The core benefit touted by this architecture is the promise of modular, linear scale. When a certain sizing threshold is reached for compute and/or storage performance/capacity, you simply purchase one or more additional nodes identical to your existing nodes and add them into the cluster using the HCI management software that comes with the solution. Sounds great, right?
There are two inherent problems with hyper converged infrastructure architecture from a Total Cost of Ownership Perspective:
1.Server Workloads are Typically Not Balanced – HCI Compute and storage resources are rarely, if ever, consumed in a balanced manner. Therefore, you will almost always be adding unnecessary compute resources when you need more storage resources or vice versa.
2. Inflated Enterprise Software Licensing Costs – Since every CPU core in an HCI cluster services both compute and storage requests, you must license every CPU socket and core in the HCI cluster.
Sample Scenario: Enterprise Application Environment using Microsoft SQL Server
We encourage you to do more research, talk to more experts, and give us a call if you have any questions or want to discuss whether a hyperconverged infrastructure is right for you. It will certainly save you money and countless headaches!