In an attempt to reduce cost or improve performance at scale, some organizations are introducing low functionality, shared or cloned desktop operating systems within their virtual desktop environment. This article sets out to show that this approach is flawed, is simultaneously limiting and unnecessary and that it increases operational risk and reduces agility. New developments in virtual storage support and virtual desktop management ought to consign shared or cloned desktops to history.
The reduction of risk and simplification of IT is a key precept of the best enterprise architectures. Flexibility of deployment, the ability to take detailed design decisions as late as possible and a need to absorb unplanned application and software changes without any impact on underlying infrastructure designs is a critical success factor for any agile organization. The more complex and fragile an underlying infrastructure design is, the more likely it is that change at a higher level will cause complexities in implementation, delays or worse still, total incompatibilities, resulting in yet another silo of technology to support.
There are two basic approaches to delivering virtual desktop environments, rich, fully persistent desktops (the user has her own operating system and may configure it just like their corporate desktop) and limited functionality linked clones (also known an non-persistent) on desktops where third-party software breaks the operating system into components and then rapidly reassembles them again at run-time. Rich, fully persistent desktops can be treated just like the desktop you already have on a physical device, you can install your own software (subject to corporate policy), suspend operations in one location and pick up again in another, and have a full personal computer user-experience with the emphasis on “personal”.
The linked clone approach make compromises to reduce cost and improve performance by reassembling shared components of the desktop operating system with personal (and sometimes group) components to create a new, fresh desktop every time you log in. Many of the personal features and benefits of having a persistent desktop are compromised out. You can no longer suspend and resume at a different location because the desktop is rebuilt every time and that spreadsheet you were in the middle of editing isn’t there any more. Installing applications becomes a big job for the IT Department as new and changed applications all have to be regression tested and integrated into a large and highly complex application library. New operating systems and operating system versions might not be available immediately as the integration of these is complex and needs significant integration testing. Having a few versions of Windows XP still hanging around or a couple of Ubuntu Linux instances for a developer are just too hard to implement so may end up in their own infrastructure silo. In summary linked clones are a compromise too far, sacrificing flexibility and risk against cost and performance and will result in a much more complex infrastructure architecture that actually increases cost.
Simple is good. Designing a virtual desktop environment with fully persistent desktops enables organizations to take a single approach to desktop management (such as Microsoft System Center 2012, leveraging skills, tools and processes you already have to manage security, patching, configuration and support across your virtual and physical estate alike. Vendor support for application and operating system compatibility is not compromised and your IT department faces many fewer challenges to ensure operational integrity in the physical and virtual world. Work to test and configure platforms, applications and processes needs only be done once, organizations can reuse vendor and other third-party recommended best practice frameworks and tools.
Flash based virtual storage technology such as the GreenBytes vIO delivers zero latency data reduction capability to the infrastructure you already have, delivering rich, fully-persistent desktops in less storage and at less cost than cloned or shared desktops. By using the storage layer to enable storage performance improvements and cost savings we avoid dragging these constraints into higher layers of the stack and the resultant solution is simple and works with all client operating systems, version and variants delivering a fully compatible, robust and flexible virtual desktop platform without compromise.