When it comes to virtual desktop infrastructure, IT professionals should go for the gold—the golden image, that is. A single desktop image centralizes the processes of patching, upgrading, managing and securing virtual desktops. If any mistakes are made along the way or when companies’ circumstances inevitably change, it’s easy to make the necessary system changes when there is one master image.
A golden image is typically used in the non-persistent VDI model, also known as pooled VDI. With persistent, or personal, VDI, each employee’s desktop runs from a separate, customized disk image. Individual settings are saved and appear each time an employee logs in to the machine. With non-persistent VDI, desktops are built from the golden, or master, image. Employees receive a “fresh” image each time they log in, and nothing is saved once they log out. Non-persistent VDI tends to work best for task-oriented users, such as call center workers or support staff.
There are some complex organizational and technological issues related to the creation of golden disk images and their use in both persistent and non-persistent environments, but here are a few key things to keep in mind:
1. Keep the image as simple as possible.
The more you add to the image, the more you have to manage. The image should include the desktop operating system and the applications most commonly used in the organization. Depending on the number of people accessing the master image and the tasks they need to perform, it may make sense to leave out productivity applications. If too many applications or too many versions of applications are included, the golden image will become bloated. Application virtualization and publishing technology can be leveraged as an alternative.
Some companies also develop a collection of golden images based on employees’ roles and/or the tasks they are required to perform. Be careful not to develop so many images that it results in image sprawl, counteracting the benefits of virtualization.
2. Be mindful of application versions.
When creating the golden image, it may make sense to upgrade to the latest version of applications. You will have to figure in employee training time, especially if the new version is markedly different. Avoid making a transition to VDI and updating applications all at the same time – that can be too much change at once for people.
3. Check for application licensing issues.
Licensing costs can be tricky to calculate, depending on your company's requirements and your VDI vendor's specific pricing models. For example, with Microsoft Windows systems you need to understand the implications around Software Assurance, Virtual Desktop Access and Companion Device Licensing. Check with the vendors of all of the applications you intend to virtualize to ensure that the model will be cost effective over time.
4. Don’t get caught short on security.
VDI, especially non-persistent VDI, has inherent security benefits due to the centralization of computing resources and the standardization of the image. However, that doesn’t mean users and their devices are immune to security issues. Be sure to apply all security best practices to the OS instance on the master image, and include your organization’s security safeguards, such as anti-malware software.
5. Use “standard” desktop settings.
In a PC-based environment, each employee’s desktop settings have likely been tweaked to individualize the user experience. When setting default desktop settings on the golden image, implement those that are most common across the organization to create a standard environment.
VDI is not a simple technology, and these are just a few of the many considerations IT departments must make about reference images when transitioning to a virtualized desktop environment. At the same time, VDI technology is advancing at a rapid pace, and vendors are continuously adding features that overcome many of the challenges VDI has faced in the past. Remember the golden rules, but maintain a flexible mindset in order to fully exploit VDI now and in the future.
Underwritten by HPE NVIDIA, and VMware.
