Demystifying VMware and the Modern Appliance

When you hear the word “appliance”, what do you picture? For most people, the first images that spring to mind are home appliances, like the washing machine or dishwasher.

The question is, how does the word “appliance” translate in the business world? Interestingly, while the usage is obviously very different, the broad definition is the same. It’s a self-contained solution that performs a specific purpose, delivering better performance with less complexity than what you could achieve using standard hardware and software. In short, there are horses for courses – going back to the kitchen analogy, none of us would think of putting our coffee cups in the washing machine or our jeans in the dishwasher!

Faster routing with a task-focused user interface

In the IT world, a developer might design, for example, a modified and specialized Linux kernel and surrounding software to make traffic routing decisions faster than a standard operating system (OS) installation.

Typically, the appliance has a simplified and task-focused user interface that restricts the configuration choices available compared to a traditional OS install. Quite often, the appliance uses custom or uniquely configured hardware and the appliance software will only run correctly on the physical appliance, using the factory configuration and approved hardware. Again, we can see some parallels with the home appliance world.

Flexible packaging and redundant solutions

In terms of packaging, the solution might be assembled as a single compute element, say a traditional one or two U-rack server. In some cases, a single server might not have enough horsepower to handle the required tasks and you might need to spread the workload across multiple nodes to achieve the design goal.

Alternatively, the solution might use multi-nodes for redundancy, delivered in a multi-node converged infrastructure. This means that all inter-node communications are contained within the physical solution with the complexity hidden from the customer.

Why virtualize?

In some cases, an appliance maker will forego the hardware and instead release an encapsulated virtual machine (VM) image. This is a great way to allow a customer to test drive a software stack and see if they like the feature set. This approach also allows the appliance vendor to create a single image that can run on multiple hardware platforms.

Smooth operation

There’s another important benefit to adopting virtualization technologies on your appliance. Quite often, an appliance is made up of several very complex functions that work together in tandem to perform the workload expected of the appliance. By putting each function into its own container, boundaries can be created to ensure the smooth overall operation of the appliance.

For example, hardware resources such as number of cores, memory, and disk space can be locked to specific functions, which ensures that all other functions have the resources they need to perform their tasks. The host OS (or hypervisor) acts as a supervisor, keeping each function limited to its assigned resources. Splitting the software solution into individual functions also delivers an architecture with more clearly defined interface touch points amongst the various components or functions.

High availability

Another advantage is that if one of these functions has an issue or crashes, the effects of the crash are limited to that single component, which can be independently restarted. This means that the solution can continue to operate without any noticeable interruption. Multiple copies of the component can also run simultaneously, allowing a rapid fail-over from one component to a backup copy.

Scalability

The beauty of this design philosophy allows the solution to be spread across multiple nodes, quickly and easily scaling from a single low-end box solution to a large rack level appliance, consisting of dozens of nodes.

Consistency across platforms

Even better, the virtualization running on the hardware can abstract subtle changes between the hardware platforms to provide a consistent environment for the OS. This translates into lower development costs since large parts of the validation process conducted on one platform can be leveraged on others.

Vendors can also benefit from the work done by Dell EMC OEM and VMware.  The VMware Hardware Compatibility List (HCL) provides details on servers, which have been validated to function consistently and properly with VMware. This frees up the appliance creators to focus on what’s important and unique about their solution.

A hybrid approach

So, what’s it to be – hardware solution or virtualization? Interestingly, I’m now seeing a growing trend in the appliance industry, where vendors are adopting a hybrid approach to these delivery methods.  Many are still using the physical machine approach or cluster of nodes, but are also adopting virtualization technologies as a software foundation that runs on the appliance.

Additional security and simplified lifecycle management

For example, VMware on Dell EMC OEM appliances allows your solution to run multiple operating systems on one physical machine. It adds fault and security isolation at the hardware level, and makes it easy to move and copy virtual machines. It also simplifies lifecycle management as there is an easier transition between hardware generation changes. In addition to helping your solution to become cloud ready, VMware also has solutions that can make containers and virtual machines work together with minimal effort.

Better together

In my view, this hybrid approach delivers the best of both worlds. Vendors can completely control the hardware and know exactly how it’s configured and what its capabilities are, but at the same time, they are free to treat the platform as an environment that “just works.”