Building a User State Virtualization Plan

This post is from A.J. Smith, our product manager for User State Virtualization

Today, Karri Alexion-Tiernan posted a blog on the Windows For Your Business site about the value of User State Virtualization (USV), so I thought I would go a level deeper to talk about how USV has changed with Windows 7 and share some thoughts on what you should consider when looking at USV in your organization. I’ll also share a few tips on integrating USV with other Desktop Virtualization technologies.

Before we jump in, let’s spend a minute to level set everyone on User State Virtualization. USV is made up of three features, Roaming User Profiles, Folder Redirection and Offline Files in Windows 7 Professional, Enterprise and Ultimate.

• Roaming User Profiles give you the ability to store your Windows profile information (eg. files stored in C:\users\”username”) in a network shared folder which is then downloaded when you log into a computer.
• Folder Redirection is configured using Group Policy to redirect specific folders in a profile like Desktop and My Documents to a network shared folder. Redirecting folders is an easy way to reduce the size of a Roaming Profile.
• Offline Files, enabled by default in Windows 7, provide users the ability to work with their redirected folders and other network shared content when disconnected by storing local copies of files on their PC. Any changes to the files they are automatically synced back the next time they are connected.

In Windows 7, a number of improvements have been made and USV has evolved from the last time you might have looked at it under Windows XP, so I definitely suggest you take a look at it now as part of your Window 7 migration.

The first improvement is related to Roaming User Profiles in Windows 7. You can now synchronize your user registry hive stored in NTUser.dat via Group Policy. Once the policy is enabled, you can set a time interval or a specific time of day for the synchronization to take place. Both options have a one hour random offset to make sure that every machine does not upload at the same time. In the past, synchronization only happened at logout - the new policy capability is important because it ensures that even if a user doesn’t logout, very often their user settings in the registry are backed up regularly, preventing any loss.

With Folder Redirection under Windows 7, there are thirteen folders that can be redirected, compared to Windows XP, which has five. We heard from customers that they needed more flexibility in what could be redirected because users were storing their data in more places. With these improvements, IT can reduce the size of the roaming profile even further.

Offline Files in Windows 7 does a great job of transitioning from online to offline modes and synchronizing files, making it more likely that files will be up to date on the machine and the network share. If you want to learn more about what is new with User State Virtualization, Wole Moses did a great post a few months back on this. You can also check out the User State Virtualization section on the TechNet Desktop Virtualization page for more technical info.

When organizations start thinking about implementing USV, the big questions I hear are “How do we get started?”, “What users should I target”, and “Should I use all of the features in USV?” One of the best resources in helping with these questions is the Infrastructure Planning and Design guide for User State Virtualization. This guide breaks down the process into five steps:

1. Assess user data requirements
2. Assess user settings requirements
3. Evaluate compatibility considerations
4. Evaluate different usage scenarios considerations
5. Evaluate infrastructure and manageability requirements

The first step is to assess the user data requirements and the guide walks you through determining which folders and data are important to your business. You need to think about what folders in the profile have data that you care about (My Documents, Desktop, etc) and which ones you might want to exclude (Do you really want to redirect Saved Games and My Music?). It also has you review considerations like logon and logoff times, if you plan on having users logged into more than one computing session at a time, performance and the load of networks and servers, and how you want to handle the AppData\Roaming folder. These considerations and having an understanding of what folders and data your users need access to will help you determine what USV features you need to implement for user data.

User settings like network drive mappings, printer connections, taskbar location, and dictionary and spelling checker options in Microsoft Word are usually stored in two locations - the AppData/Roaming Folder and in HKCU portion of the registry. You can also control some of the settings found in HKCU, such as which desktop themes should be used, the taskbar settings, and what desktop icons should be on the user’s desktop though Group Policy and Group Policy Preferences. Step two helps you determine if you can use Group Policy, Preferences and Folder Redirection (with or without Offline Files) to virtualize content in AppData/Roaming to create a desktop experience or if you should use Roaming User Profiles to provide access to all of the user’s personalization's.

In most Windows 7 migrations one thing I hear a lot about is compatibility, and with USV you need to think about this too. Most companies I talk to are moving from Windows XP to Windows 7 and if you look at the profile namespace, there have been some significant changes making the two profiles incompatible. This makes step three very important to organizations that used USV in Windows XP and will impact users that roam between Windows XP and Windows 7 machines. Step three also makes you think about platform compatibility. If you plan on having a mix of 32-bit and 64-bit versions of Windows 7 and have 32- and 64-bit versions of the same application, you need to think about how they store their data and settings in AppData/Roaming and HKCU. Some applications might store information differently and in different locations depending on their platform.

Step four makes you think about your users and their roaming habits. We see three types of users in most mid to large sized organizations.

1. Assigned computer users –Sales people with dedicated laptops or an accountant who uses the same computer in their office day in and day out.
2. Occasionally roaming users – Hospital administrators who are usually in their office but occasionally need to use a computer at a nurse’s stations.
3. Always roaming users – Call center employees who use a pool of machines or nurses who roam from floor to floor and room to room using machines at nurses stations and in patient rooms.

Each set of users will have different needs and this step has you think about questions like “Should I use Offline Files for the accountant who uses connected computer all day?”, “Do I allow roaming profiles to be used on kiosk machines?” and “What mode should you run Outlook in for each set users?”

The fifth step has you assess your infrastructure and manageability requirements. Here you need to evaluate your network bandwidth and latency since this will influence your use of Offline Files and the configuration of the slow link mode Group Policy. This step will also have you think about using Failover Clustering and Distributed File System (DFS) to increase availability, redundancy of the data, and settings. Lastly, you need to consider if you need content indexed by Windows Search so it can be quickly discovered.

All five of these steps apply to rich or virtualized desktops. If your organization is evaluating Desktop Virtualization, there are additional considerations that you should think about.

• If you are evaluating Microsoft Application Virtualization (App-V) and you want the user specific application settings stored in “C:\Users\[user name]\AppData\Roaming\SoftGrid Client” to follow the user to different desktops, you need to enable Folder Redirection for the AppData\Roaming folder or use Roaming User Profiles.
• With session based desktop on Terminal Services or Remote Desktop Services, consider what the user needs access to in that session. Are they accessing just one application through Remote App or are you providing an entire desktop? Do you really need to use Roaming User Profiles on these sessions and can you set a mandatory profile to lock down the environment and maximize performance?
• If you are using VDI to centralize desktops, you will need to consider how it will be implemented. Do you have a pooled model where you use a VM for a short time and when you’re done with it someone else can use it or do you have a personal/dedicated model where you have one VM that you access all the time and nobody else uses it? If you are running in the personal/dedicated model, you should consider the same USV features that you would provide to the Assigned Desktop Users in step four. If you are using the pooled model, consider what folders to redirect and if you need to roam settings in HKCU through Roaming User Profiles. I would not recommend using Offline Files for either session or VDI based desktops since you have a constant network connection to any network folders. For more information on USV in centralized desktop scenarios, review Appendix D of the Infrastructure Planning and Design guide for User State Virtualization.

USV helps you find the right balance between the control of centralized management and providing the flexibility end users need. Finding this balance takes a bit of work but can pay off greatly with more productive end users and better data control for IT Pros. If you want to learn more about USV, check out the USV section of the Desktop Virtualization Zone on the Springboard Series on TechNet.