BACKGROUND IMAGE: iSTOCK/GETTY IMAGES
Converged and hyper-converged infrastructure make it easier to support VDI and desktop virtualization because they're...
built to install simply and run complex workloads.
Converged infrastructure (CI) brings the four core aspects of a data center -- compute, storage, networking and server virtualization -- into a single chassis. Hyper-converged infrastructure (HCI) adds tighter integration between more components through software.
With both CI and HCI, you know for sure that all the components are compatible with one another, and you can supply your shop with the necessary storage and networking that are so important to VDI in one fell swoop. This helps reduce the complexity of deploying VDI, an advancement that many shops looking to virtualize desktops would welcome.
As helpful and innovative as the technologies are, however, they also bring up some questions, such as what they do and how they differ. Well, it's time to put any confusion to rest. Let's sort through the features of converged vs. hyper-converged infrastructure, and identify the differences to understand what makes each one important to desktop virtualization administrators.
What is converged infrastructure?
Converged infrastructure brings compute, storage, networking and server virtualization into a single chassis that you can manage centrally. This can include VDI management, depending on what configuration you buy and from which vendor.
The hardware you get in your CI bundle is pre-configured to run whatever workload you buy it for -- whether it's to support VDI, a database, a specific application or something else. But you don't have much flexibility to alter that configuration after the fact.
Regardless of how you build out a VDI environment, be aware that it is expensive and time consuming to scale up after the fact. Adding components separately becomes complex, taking away from many of CI's benefits. And adding desktops and capacity to in-house infrastructure can be just as expensive, which speaks to the importance of proper planning for any VDI deployment.
The pieces of your CI bundle can also stand on their own, however. A server you purchase in a CI bundle functions just fine without the other infrastructure components you bought with it, for example.
What is hyper-converged infrastructure?
Born from converged infrastructure and the idea of the software-defined data center (SDDC), hyper-converged infrastructure takes more aspects of a traditional data center and puts them in one box. It includes the same four aspects that come with converged infrastructure, but sometimes adds more components, including backup software, snapshot capabilities, data deduplication, inline compression, WAN optimization and more. CI is mainly hardware-focused, and the SDDC is usually hardware-agnostic; HCI combines these two aspects.
HCI is also supported by one vendor and allows you to manage everything as a single system through a common toolset. To expand your infrastructure, you simply snap boxes of the resources you need, such as storage, to the base unit as you go.
Because HCI is software-defined -- which means the infrastructure operations are logically separated from the physical hardware -- the integration between components is much tighter than you see with CI, and the components have to stay together to function correctly. That makes HCI suitable for even more workloads than CI, because you can change how the infrastructure is defined and configured at the software level and manipulate it to work for specialized applications or workloads that pre-configured CI bundles can't support.
Hyper-converged infrastructure is particularly valuable for VDI because it lets you scale up quickly without a ton of added expense. That's not the case in traditional VDI settings; shops either have to buy more resources than they need in anticipation of scaling up, or wait until virtual desktops eat up the allocated space and network, then add infrastructure after the fact.
Both those situations can be expensive and time-consuming to resolve. But with HCI, if you need more storage, you can just snap that onto your stack. You can scale up in the time it takes for you to get another box, rather than going through an entire re-assessment and re-configuration of your in-house infrastructure.
Additionally, when you make the switch from physical PCs to virtual desktops, you still need something to do all the processing that laptops and desktops once did. Hyper-converged infrastructure helps with this because it often comes with a lot of flash, which is great for virtual desktop performance. It improves I/O, reduces the effects of boot storms, and lets you run virus and other scans in the background without users ever knowing.
The flexibility of hyper-converged infrastructure makes it more scalable and cost efficient than CI because you can add blocks of compute and storage as needed. The upfront costs of both technologies are steep, but in the long term it can pay off.
Don't be fooled by the converged infrastructure hype cycle
Should you try hyper-converged storage for VDI?
Hyper-converged infrastructure can simplify your virtual environment
How hyper-converged infrastructure market leaders compare
How HCI, CI products will evolve in 2017