Cache Roaming for Virtual Sessions

Cache Roaming functionality introduces capabilities to roam user application caches between sessions in non-persistent environments. The Virtual Hard Disk (VHD) container is attached to the user's virtual desktop or session allowing the necessary folders within the user profiles to be redirected here. The feature is suitable for supported VDI infrastructures in virtual desktop environments, such as XenDesktop, or Remote Desktop Session Host (RDSH) scenarios, such as XenApp. Applications do not require any reconfiguration and no changes are made to user profiles.

The feature uses two actions to achieve this:

Manage VHD - Mount an existing VHD or create and mount a new VHD.
Cache Roaming - Redirect a user profile cache to the VHD.

The two actions can be used independently but most commonly, they will be used together - roaming the VHD specified or created using the Manage VHD action, to the location defined in the Cache Roaming action. The actions are available on Pre-Desktop and Desktop Created triggers, and automatically detach on logoff and network disconnect. This allows users to reconnect when they log on to another endpoint or start a new VDI session. VHDs can optionally be detached on session locked and session disconnected and can be added to reusable nodes for use on the compatible triggers.

One of the main use cases for this functionality is the roaming of Outlook OST Cache files, providing users instant access to their Office 365 mailboxes. Outlook Cached Exchange requires large OST files to remain resident within a user’s profile. In Non-Persistent VDI and RDSH environments, the profile is typically rebuilt at logon, resulting in the loss of user's OST files. Consequently, at the next logon, Outlook has limited functionality while it downloads and rebuilds the OST cache, which can be multiple gigabytes in size. Using this feature means that users with non-persistent VDI setups do not need to be in ‘Exchange Online Mode’ - they can be in ‘Cached Exchange Mode’, persisting their entire mailbox between sessions. This provides a much better user experience and can make users instantly productive following migration to Windows 10 or Office 365 migration.

In addition to Outlook OST Cache files, the Manage VHD action includes built-in settings for roaming OneNote, OneDrive, Windows and Outlook Search, and Skype for Business 2016/365 Global Address List caches. Additionally, you can also create your own custom redirections. Example locations that would be potential candidates are areas within the user profile that are too large for synchronization via Environment Manager Personalization, but are key to providing an optimal user experience.

OneDrive Cache Roaming

To provide a seamless user experience without major impact to system performance, Environment Manager provides a policy method of persisting user profile settings across virtual sessions for OneDrive. The template used for OneDrive cache roaming utilizes a filesystem redirection driver and requires slightly different configuration to the other templates provided. Once configured, at user logon the VHD is mounted (or created if it does not already exist). The user's OneDrive cache is redirected to a sub folder at the root directory of the VHD. When the user logs off from their sessions the VHD is automatically detached and re-mounted at the next logon.

Windows and Outlook Search

Environment Manager supports roaming both the Windows and Outlook search indexes via built-in cache templates:

•Outlook Search template

The Outlook Search template enables a per-user profile of the Outlook search index to be roamed between non-persistent sessions. The template delivers real improvements for users, avoiding the need to download and rebuild the search index at every user logon.

Note, if a mandatory user requires a persistent Outlook search index cache they will need to select both the Outlook OST and the Outlook Search cache templates.

•Windows and Outlook Search template (single user workstation)

The Windows and Outlook Search template enables the roaming of system-wide Windows Search database between sessions on a single user workstation. Using the template, the search index is delivered from a locally stored directory.
Note, there is no support for the template on concurrent sessions on Windows Server.

The use of both the search index cache templates together is not supported.

Concurrent users

Environment Manager now supports concurrent user access for Office 365 VHD containers. This enables a user within a non-persistent Windows environment to have multiple sessions running at the same time, for example to access Outlook from multiple virtual sessions.

The Windows Office 365 environment allows multiple concurrent sessions but only one connection to the cloud based storage. To enable multiple concurrent sessions, Environment Manager creates a VHD for each device logon. Each VHD will synchronize with the cloud based storage, ensuring that files are always updated. When a user logs out of a session, the VHD is detached, unlocked and becomes available for another user session. A user can create many concurrent sessions.

At logoff from concurrent sessions, a maximum of 5 VHD files are retained per user. This ensures that users have a pool of synchronized VHDs available to re-attach and from which to restore the Office 365 cache.

Manage VHD

Select or add a node on the Pre-Desktop or Desktop Created triggers.
From the Actions ribbon, select VHD > Manage VHD.

The Manage VHD dialog displays.

Complete the fields to set up the action:

Setting	Properties
VHD File	Select or enter the path and filename of the VHD to be mounted. If the VHD does not exist on an endpoint and the Automatically create VHD if it does not exist option is selected, a VHD will be created in accordance with the settings configured in this dialog. VHDs should not be created on pre-existing mapped drives. The VHD File location will typically be a UNC path to a folder that the user already has full access to, for example a User Home Folder location. For advice on how to configure permissions on the VHD Network folder, we recommend customers review Microsoft best practice for Home Folders as a baseline here https://support.microsoft.com/en-us/help/274443/how-to-dynamically-create-security-enhanced-redirected-folders-by-usin This ensures that Domain Administrators and the Current User have Full Control on the VHD file, with the User being the Owner of the Parent Folder.
VHD Root Folder	The root directory of where the VHD will be mounted. The folder will contain the VHD contents such as Outlook PST files or the OneDrive cache for example, and can be accessed like any other folder. This enables redirected folders to be managed in a common location.
Automatically create VHD if it does not exist	If the specified VHD does not exist on an endpoint, one will be created with the settings defined in this dialog.
VHD Type	Fixed - The size of the disc is determined on creation - it will always be the size set in the Max Size field. This offers better performance than Expandable VHDs but can have a negative impact on logon times. Expandable - The size of the disc is variable and will grow to the maximum size as data is added.
Max Size	The maximum size of the VHD between 150MB and 2TB. Even though each user is provided with 1TB of free OneDrive for Business storage with Office 365, it is not necessary to set the Max Size of the VHD to 1TB as it is unlikely this full allocation of disk space will ever be used. However, the Max Size can be configured on a contextual basis, using Policy Conditions, to meet individual user needs.

Cache Roaming

Select or add a node on the Pre-Desktop or Desktop Created triggers.
From the Actions ribbon, select VHD > Cache Roaming.

The Cache Roaming dialog displays.