Product Documentation

Citrix App Layering 4

Jul 20, 2017

Welcome to application management simplicity

Citrix App Layering makes it easier to manage your Windows applications. Citrix App Layering can help you manage your applications and operating systems regardless of which hypervisor or provisioning service you use.

Citrix App Layering separates the management of your operating system and apps from your infrastructure. With Citrix App Layering you can install each of your apps and operating system patches once, and then use them as part of any image you deploy. You can publish Layered Images as open standard virtual disks usable in any environment. This allows you to maintain a single Windows installation, and a single copy of each application, that you use for all of your images across all of your virtual environments.

  • Citrix App Layering wraps each of your applications in a Layer, and stores the Layers as virtual disks.
  • You can pull together any combination of these App Layers and an OS Layer as part of a Layered Image, and publish it to your target platform.
  • That means that you can install an application or OS once, and deploy it as part of any number of images.

Provision servers in any environment

Citrix App Layering lets you to package any Windows app as a virtual disk Layer and deliver it, installation-free, to session hosts. With Citrix App Layering, you can:

  • Install and manage a single copy of your Windows OS and a single copy of each of your apps in Layers.
  • Select any combination of Layers to create Layered Images that are deployable as Session Hosts.
  • Deploy those Layered Images to virtual machine session hosts, making the applications available to users.

New applications, application updates, and Windows patches can be delivered to an entire RDSH farm with a single image update.

Deliver applications with ease

You can Layer Applications and deliver them as read-only virtual disks, which you can use to:

  • Add the app to one or more Image Templates that you can then use to publish Layered Images and use them to provision session hosts or desktops.
  • Elastically assign apps to users, who will see the apps on their desktops upon login.

Layering is faster and easier than app virtualization and is compatible with more apps. Layers have the look and feel of a local installation and enable full application interoperability.

Each App Layer contains the OS Layer you want to use for your Layers and Layered Images, and the application itself, installed, configured, and in the state in which you want users to encounter it upon login.

The OS Layer is the first layer you create, because it is required for creating App Layers, Platform Layers, and Image Templates. Using the same OS for all of your layers and images means that you can patch an OS layer once to update it everywhere. For example, after one OS update, an administrator can republish the images for an entire server farm!

Delivering App Layers as part of Image Templates, which are then published as Layered Images.

Layer platform tools and software to hold infrastructure-related software and settings. This allows you to maintain platform-independent OS and App Layers.

Provision RDSH VMs. You can create custom RDSH virtual machines by assigning any combination of compatible OS and App layers in any order.

Delivering App Layers as Elastic Layers

You can deliver one of more of your App Layers to users as Elastic Layers that appear on the user's desktop when they log in, no reboot required! The apps appear to be locally installed even though no installation procedure is run on the desktop. Elastic Layers provide a custom application experience on top of non-persistent virtual desktops (VDI) and Citrix XenApp and RDSH sessions.

Elastic Layers are App Layers that have been elastically assigned to Active Directory Users and Groups.

To use Elastic Layering, you turn on the Elastic Layering feature for one or more of your Image Templates so that the resulting published Layered Images support the delivery of Elastic Layers to users who have login permissions. The virtual disks representing Elastic Layers are mounted based on Active Directory User and Group assignments when users log in.

Based on patented file system and registry virtualization technology, you can use fewer published desktop and application silos and fewer desktop pools to deliver custom user work spaces. For example, Joe can login to VMware Horizon Pool 1 and receive his 10 applications. Sally can then login into the same VMware Horizon pool and receive the same 10 applications as Joe but also Adobe Acrobat Pro. Likewise Tom can login to his Citrix XenApp desktop from Silo 1 and receive 3 applications. Janet can then log in to the exact same XenApp server in Silo 1 and receive the same 3 applications as Tom plus QuickBooks and Microsoft Project.

User (personalization) data and settings (App Layering Labs)

The User (Personalization) Layer, a feature still in App Layering Labs, is a writable layer that captures the user's local profile changes, user-installed apps and plug-ins, and locally saved data. The User layer supports Windows 7 and Windows 10 OS Layers only. It lets you deliver fully persistent Windows work spaces using non-persistent, pooled virtual desktops. Instead of having to allocate a virtual machine for every user who needs a persistent experience, you can size your infrastructure based on the maximum number of concurrent users, significantly reducing server and storage costs.

A simple addition to your environment

The heart of the Citrix App Layering deployment is the App Layering appliance (aka Enterprise Layer Manager), a virtual appliance that you deploy in your environment. The App Layering appliance hosts the App Layering Management Console, a friendly interface where you create Layers, and then assign them to either Layered Images, or directly to users via Elastic Assignment.

With App Layering you can create OS, App, and Platform Layers once, and use them to create any number of Image Templates from which you can publish Layered Images. You can then update the OS, app, or Platform software by adding a new Version to the Layer for each patch or update that you apply.

In App Layers you can deploy virtually any applications compatible with the OS. Each App Layer can include one or more applications. When it's time to upgrade an application, you can add a new version to the Layer for the latest update.

Platform Layers are designed to support your environment. A Platform Layer containing your hypervisor tools and settings makes it easy to create layers using VMs in your hypervisor environment. A Platform Layer containing your hypervisor, provisioning service, and connection broker software isolates App and OS Layers from the infrastructure where they will be published.

Layered Images for provisioning Session Hosts and servers

Image Templates are where you choose the Operating System and Layer assignments for an Image. You can include OS and App layers in any number of Image Templates. Using an Image Template and a Platform Layer, you can publish a Layered Image to your provisioning service, hypervisor, or network file share .

You can publish Layered Images as virtual disks to any location to which the appliance has access, and use the disks to provision as many servers as you need.


A Connector configured with the credentials for a specific location in your virtual environment, allows Citrix App Layering to publish the Layered Images and provision servers in a specific location.  


For compatibility details, see System Requirements.