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Persistent virtual desktops tend to be more difficult to manage than nonpersistent virtual desktops, because they retain user settings and data, making them more akin to physical desktops.
Each time a user logs in to a persistent desktop, he connects to the same virtual desktop that includes his specific settings, configurations, screensaver and more. This is the VDI equivalent of a user having a personal PC. In contrast, a nonpersistent desktop is a virtual desktop often shared among several users that resets to a pristine state at the end of each session. That makes remote desktop management simpler, because administrators don't have to worry about maintaining users' settings and data through updates and any potential problems.
Each VDI software vendor has a slightly different approach to desktop virtualization, but the difference between managing persistent and nonpersistent desktops doesn't change. As a general rule, nonpersistent desktops are easier to manage than persistent desktops, because admins can use only one golden desktop image, which they share among all users. Write operations redirect to differencing disks that purge any customizations at the end of each session. Sharing a single image means admins only have to update and secure one virtual desktop environment.
Some organizations use separate virtual desktop images for each employee, even when they're all using nonpersistent desktops. In these types of environments, a connection broker links user-session requests to an available virtual desktop. These environments are similar to the golden-image model, using differencing disks to temporarily store changes to the desktop and then erase them at the end of the session, just with multiple versions of the same desktop. When admins need to update nonpersistent virtual desktops, they update the golden image and then redeploy the users' desktops with the new image.
With persistent desktops, maintenance is more similar to a physical PC environment. Persistent virtual desktops contain users' personal data, so admins can't simply overwrite the base image each time they need to update the desktop. As such, administrators have to push updates to each individual virtual desktop operating system. Still, some admins may actually feel more comfortable managing persistent desktops, because they can treat them just like physical PCs.
Remote desktop management with persistent desktops is more complex, though, because IT has to manage several different images and their storage requirements. The master image for an entire deployment of nonpersistent desktops can sometimes take up less storage than the disk image for a single persistent desktop because of all the extra user-specific data. Storage technologies have improved, so admins can usually support persistent desktops at a reasonable cost, but it does add another resource administrators need to manage.
The case in favor of persistent desktops
When should you use persistent VDI?