How Liquidware Labs FlexApp tackles application layering

For all the security and management benefits of delivering applications rather than full virtual desktops, it can often cause too much app isolation. FlexApp tries to find a balance between IT's competing interests.

Liquidware Labs FlexApp lets IT deliver remote applications that run as if they are native, without the legwork of installing and updating them on virtual machines.

FlexApp is a standalone product, but it is also included with the company's ProfileUnity user environment management platform. ProfileUnity and FlexApp allow IT to manage users' profiles, files and apps in a different storage location from their virtual desktops. Like other application layering technologies, Liquidware Labs FlexApp tries to provide a native user experience while still virtualizing the apps independent from the company's virtual desktop deployment.

App virtualization typically requires an application to run in isolation separate from the host operating system (OS) and any other applications. This approach addresses OS and app compatibility issues and reduces maintenance time. Unfortunately, this isolation makes it difficult to virtualize apps that interact with other systems, such as antivirus software, device and kernel drivers and certain plug-ins.

Liquidware Labs FlexApp basics

Instead of isolating apps, FlexApp runs them in containers on virtual disks outside of the virtual machine (VM), while still making them accessible to the OS and other applications. The layered apps behave as though they're natively installed on the VM. FlexApp helps IT operationally, because administrators can deploy applications that attach at login to nonpersistent Citrix XenDesktop or Horizon View virtual desktops. This allows IT to manage as few as just one master image for its virtual desktop deployment.

When implementing FlexApp, IT can choose from two models: department-installed applications (DIA) or user-installed applications (UIA). IT can use FlexApp DIA to implement applications for specific groups of users, and UIA grants selected users the right to install their own applications. The FlexApp DIA model is more common because hundreds of users can share a single copy of a layered app without IT having to install the application in the master VM image. The FlexApp UIA model is meant for small subsets of users, where individual installations might be more expedient.

Instead of isolating apps, FlexApp runs them in containers on virtual disks outside of the virtual machine.

FlexApp can support physical machines running Windows XP, 7, 8 and 10, or server-based computing environments such as XenDesktop, Horizon View or Microsoft Remote Desktop Session Host. FlexApp supports hypervisors such as Citrix XenServer, VMware ESXi, Microsoft Hyper-V and Nutanix Acropolis. IT can also use FlexApp with app isolation tools such as VMware ThinApp and Microsoft App-V. This last option is handy when only some apps need isolation, such as legacy programs, but IT wants to use layering as the primary app delivery mechanism.

FlexApp is fully integrated into ProfileUnity, which provides IT with a centralized console for separating data, apps and user profile settings and policies from an underlying OS. If IT is also using ProfileUnity, users' profiles, data and apps all attach to their virtual desktop at login. ProfileUnity is integrated with Active Directory, which allows IT to use user account data from the company's AD domain controllers. Admins can also use the separate application rights management configurations in ProfileUnity to control which users can run or install all of the company's managed apps, whether layered or virtualized using other products.

An inside look at FlexApp

FlexApp supports a substantial number of applications that are otherwise tough to virtualize, including apps with multiple dependencies, such as Microsoft Office or Adobe Creative Suite, and complex programs that use file system drivers and services.

FlexApp applications install in portable layers, meaning administrators can copy, paste and import them to different locations. IT can install a single app per layer, an application suite per layer or a set of related departmental apps per layer, depending on the organization's needs.

To prepare an application for layering, IT uses the ProfileUnity FlexApp Packaging Console to package the app, edit its attributes and expand the package later if necessary. Liquidware Labs recommends IT start with apps that require frequent updates, faster storage I/O performance, or disaster recovery or high availability plans.

FlexApp saves an application's binary files to a container, which can live on a virtual hard disk (VHD) or on a VMware virtual machine disk file (VMDK). VHDs are universally compatible with other systems -- including Citrix and VMware environments -- but VMDKs must live on storage accessible to an ESXi host.

Liquidware Labs FlexApp uses a pair of file system drivers to track each application within the OS file system and registry, making it appear as though the app is natively installed and part of the local file system. FlexApp also implements filters between the host OS and application layers that determine which apps to assign to users when they log in to their desktops. IT can set filters based on an assortment of criteria, such as Active Directory (AD) organizational units, OS types, connection types, computer groups or specific named users.

FlexApp won't replace Citrix and VMware's app virtualization products, but it can take application delivery to a new level, particularly when used in tandem with ProfileUnity. But Liquidware Labs is up against some heavy hitters, as the top virtualization vendors also now offer application layering: VMware includes App Volumes in its Horizon Suite, and Citrix added AppDisk into XenDesktop 7.8.

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