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VDI on Azure

FSLogix: An In-Depth Look

What is FSLogix?

FSLogix solutions enhance and simplify non-permanent Windows computing environments. FSLogix solutions are suitable for both private and public cloud environments.

FSLogix solutions include:

  • Profile Container
  • Office Container
  • Cloud Cache
  • Application Masking
  • Java Version Control

This is part of our series of articles about VDI on Azure.

In this article, you will learn:

FSLogix Licensing

FSLogix technology is included in the Microsoft licenses below:


Licenses that Support FSLogix

Microsoft 365

Enterprise 3, Enterprise 5, Academic 3, Academic 5, Student Use Benefits, Frontline Workers 1, Frontline Workers 5

Windows 10

Enterprise 3, Enterprise 5, Academic 3, Academic 5, VDA

Remote Desktop Services (RDS)

Client Access License, Subscriber Access License

FSLogix Capabilities

FSLogix introduces the concept of a profile container to redirect user profiles to a network location. The configuration file for each user profile is placed in a VHD(X) file and installed at runtime. The profile container provides the following additional capabilities:

  • Mount configuration files for user profiles on the network—this avoids the need to load user profiles and copy possibly large volumes of data, when a user logs in.
  • Limit user profile data used with Office Containers—an Office Container redirects only the specific part of a user profile that contains Microsoft Office data. This feature is useful for users working with Outlook .OST files.
  • Profile behaves as local drive—the application uses the configuration file as if it were on a local hard drive. The FSLogix solution uses a Filter Driver to prevent applications from recognizing the profile data is accessed across the network. This is important because many applications cannot be used with configuration stored remotely.
  • Cloud Cache—part of the VHD configuration file on the local hard drive. Administrators can also use the cloud cache to specify the location of remote configuration files. Maintaining a local cache with multiple remote profile containers protects users from network and storage errors.
  • Application Masking—manages access to applications, fonts, printers, or other objects. Access can be controlled based on users, IP address ranges, and other conditions.

Profile Container vs Office Container

Understanding the differences between a profile container and an office container is critical to properly using FSLogix. Office containers are a subset of profile containers. They may be used instead of profile containers (to provide more limited functionality with faster load time or performance), or in some cases, together with profile containers.

Profile Container

Profile containers are used to redirect entire user profiles. They are used in non-persistent virtual environments (for example, virtual desktops). The profile container contains the entire user profile, leaving only the data that was excluded by redirections.xml.

A profile container is conceptually similar to a Microsoft's User Profile Disk, Microsoft Roaming Profile, or Citrix UPM.

Office Container

Office containers are typically implemented as separate profiling solutions and are designed to improve Microsoft Office performance in non-continuous environments.

Compared to a profile container, the Office container redirects only local Microsoft Office user files. When configuring an Office container, you can specify which Office components you want included in the user profile (add only the components actually required by the group of users).

The data in office containers can be restored from different locations. For example, an .OST file is created on an Outlook server, from which you can recover the file if it is damaged.

Using Profile Container and Office Container Together

There are many advantages to using both profile containers and desktop containers. For example:

  • To store Office data and other configuration file data separately.
  • When an office container or a configuration file container are damaged, any remaining data will stay as is. The office container can be removed without affecting the rest of the user's settings, so that office data can be restored from the server.
  • Office containers work with profile containers to specify which office components should be in the parent container.

FSLogix Cloud Cache

Cloud cache provides a local cache that allows users to access their data even in the case of networking or storage issues. After the first read of a user profile, the cloud cache redirect users to a local configuration file, and subsequent reads are performed from there.

Cloud cache allows users to access multiple remote locations. All of them are constantly updated during a user session. Cloud cache can protect users when remote profile containers experience short-term loss of connectivity. It offers real-time "active-active" redundancy for profile and office containers.

Even if you are using cloud cache, note that all data is taken from the redirected location. Likewise, when the user writes data, writes are performed against remote storage locations, but are first recorded in the local cache file.

Cloud Caching and Login/Logout Performance

An important caveat of cloud caching is that it does not improve user sign-in and sign-out experience when using low-performance storage. In cloud caching environments, connection and disconnection times are generally slower than those using traditional VHDLocations, with the same storage. The cloud cache can only improve performance after the initial connection.

Cloud Cache Architecture

Cloud cache connects to one or more profile or office containers, identifying them using metadata. The combination of profile container and metadata is known as a cloud cache provider. The cloud cache may have one or more providers, up to a limit of 4.

Cloud cache uses a local cache file that contains a subset of the data stored in the cache provider. Cloud cache also uses local "proxy files", which are a local placeholder for the local cloud cache system. I/O operations are not performed directly against the proxy file.

The local cache file handles most read requests. Data read from the provider is stored in a local cache file, which provides future access. The local cache also writes to the file system and to all providers specified in cloud cache settings. The synchronization process is restricted by the performance of various components, including networks, remote storage systems, and clients.

Moving from Traditional FSLogix Profile Container or Office Container to Cloud Cache

You can migrate from profile containers and office containers to cloud cache. To start using cloud cache, change the VHDLocations parameter to CCDLocations. You cannot use both parameters in the same deployment.

Cloud cache providers hold the profile container as well as its metadata, while VHDLocation holds only a profile container without metadata. If a cloud cache is pointed to a profile that currently does not have metadata, metadata is automatically created, and the profile container becomes a cloud cache provider.

If the user has a profile container in multiple CCDLocations, the first profile container to appear in the CCD location becomes the cloud cache provider. All other profile containers in the same CCDLocations string are removed and replaced by the first cloud cache provider. 

FSLogix and Virtual Desktops with Azure NetApp Files

Azure NetApp Files is a Microsoft Azure file storage service built on NetApp technology, giving you the file capabilities in Azure even your core business applications require.

Get enterprise-grade data management and storage to Azure so you can manage your workloads and applications with ease, and move all of your file-based applications to the cloud.

Azure NetApp Files solves availability and performance challenges for enterprises that want to move mission-critical applications to the cloud, including workloads like HPC, SAP, Linux, Oracle and SQL Server workloads, and more.

For Windows Virtual Desktop, the availability and performance of Azure NetApp Files means you are protected from loss of your FSlogix profile containers, with a 99.99% availability guarantee and added data protection capabilities. Azure NetApp Files gives you the performance necessary to scale your virtual desktops to as large as you need, and still maintain the ever important user experience.

Want to get started? See Azure NetApp Files for yourself with a free demo.

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