First we had converged infrastructure and then hyperconverged infrastructure. If the trend continues, next up will be the ultimate hyperconverged infrastructure. As these systems continue to evolve and become more advanced, they are gaining in popularity. Very few people doubt that products from Nutanix or the newly released VMware EVO:RAIL will be huge hits. The real question is whether a hyperconverged infrastructure is right for your data center.
Before converged infrastructure, the IT world had limited choices when deploying x86-based architecture. Rack/tower units and blades were the only choices available. A common feature among these approaches is that they often used external storage to accommodate virtualization -- a common feature and a downside. Blades had an additional advantage in a shared networking, power and cooling infrastructure. Of course, the downside was that you had a higher density of servers in a single enclosure, which could increase your risk in the event of a failure. Rack servers had the advantage of separating the failure points at the additional cost of rack space and power, cooling and networking infrastructure. The middle ground between the two extremes did not exist until the introduction of converged and hyperconverged infrastructure.
Hyperconverged infrastructure in particular is looking to take the best points of the blades and rackmount servers and combine them into a better approach. This is a major step forward from most converged infrastructure solutions that marry traditional blade servers, external storage, and networking into a single consumable "block".
Compute: One of the drawbacks to blades was the high density of blades in the chassis. A single chassis failure could affect many hosts, bringing down hundreds or even thousands of virtual machines. A hyperconverged infrastructure often resembles four blade-style servers in a 2U form factor. This reduction of the possible outage footprint can be more appealing to the customer looking for higher availability. You are still gaining the benefit of data center consolidation while preserving a level of outage protection.
Networking: Connecting everything together presents a challenge in almost all environments. A rack server's ports are normally allocated for production traffic and storage. These ports come with a per-port cost, along with management overhead. In blade environments, virtual switching is often required, which adds an additional pair of switches to your environment but removes the trouble of having to cable the blades to it. A converged infrastructure does not include virtual switching and requires connections from each node to the existing switching infrastructure. This approach resembles the rack environment, just without the storage connections.
Storage: Traditional servers use internal server storage or larger external storage frames. The external storage frame enables the shared storage concept, and virtualization was quick to take advantage of the benefits shared storage enabled, including features like vMotion, load balancing and high availability. Hyperconverged infrastructure turns this on its head by using localized storage that is shared across the four hosts within the single frame or even further, across the entire cluster. This gives the advantage of shared storage without the need for the costly storage frames or the dedicated fiber infrastructure that often accompanies it. The local disk can be an enterprise-class spinning or solid-state drive, giving the converged infrastructure tremendous IOPS potential. As more converged infrastructure product vendors couple their hardware with software-defined storage abilities, the traditional storage frame designs are showing their age.
Compute, networking, storage: When you compare the benefits of the hyperconverged infrastructure over the traditional infrastructure, it's hard to not to see all of the positives (and very few negatives). Hyperconverged infrastructure has found that perfect midpoint between large blade enclosures and the single-server approach. With all of the benefits, where is the downside to going with the hyperconverged approach?
Design: When you look at your requirements and want to come to a decision about what hardware platform (hyperconverged or not converged) to go with, a key factor should come to mind: Do you plan to deploy or design in one or two deployment factors, or are you more likely to deploy in a two- to four-node method?
Nodes in a converged infrastructure are prepackaged, and knowing how you purchase is a big factor in knowing which is right for you. Converged infrastructure, by its nature, is not designed to support a single compute deployment where you would add additional compute nodes to an existing enclosure similar to a blade enclosure. The enclosure exists as a prepackaged unit that works with all of the compute nodes in the cluster.
As businesses trend toward the prepackaged approach, they also need to consider how they will approach working with a converged infrastructure.
Downside: With all the positives of a converged infrastructure, there are some downsides. The prepackaged nature of converged infrastructure is a higher investment in capital costs. This simple math would suggest it costs four times the price of a single server. However, this is a flawed assumption because a converged infrastructure also replaces some storage and networking needs. Traditional external storage frames with fiber cabling and switches are expensive.
The second downside can also be leveraged as an upside since today's IT departments are often silos of professionals responsible for defined infrastructure roles with little cross-training or responsibility. While virtualization has started to break down these IT staff silos, it is still a work in progress and moving very slowly for many organizations. Infrastructure ownership and the division of groups have deep roots in IT. Combining these silos in not simply about reducing the hardware pieces; it can also affect staffing levels. The integration of virtualization has caused some jobs to be eliminated and others expanded, but IT continues to survive and evolve, and the same will occur with a hyperconverged infrastructure. Sometimes the introduction of hyperconverged infrastructure can be the catalyst needed to break down these silo's since it often comes with management software that handles servers, storage, and some networking tasks from the same GUI.
Hyperconverged infrastructure isn't for everyone right now, with its prepackaged requirements and price. However, its ease of use and integration of storage and networking means it's only going to grow. The breakdown of separate IT silos is not a stopping point, as it is something that the business world cannot ignore even if traditional IT would like to. Just like virtualization, it is not a question of whether to use Hyperconverged infrastructure. The real question is whether you choose to adopt it soon or find yourself in a constantly shrinking pool that is having trouble keeping up.