DFS namespace folders are deleted after you restart a Windows Server 2008 R2-based computer

Symptoms

Issue 1

Consider the following scenario: 
  • You install the Distributed File System (DFS) Namespace service on a computer that is running Windows Server 2008 R2.
  • The reparse points that are configured within the default namespace setting represent the corresponding DFS namespace folders on the server.
  • You restart the server. During the startup process, the system time of the server is changed. For example, when you restart a virtual machine, the system time of the virtual machine is synchronized with the host computer during the startup process.

    Note After the system time is changed, an event that contains the system time before and after the change is logged in the System log.
In this scenario, the DFS namespace folders may be deleted unexpectedly. Without them, the DFS Namespace client computers cannot request referrals for the DFS namespace folders.

Issue 2

Users cannot access their DFS shares because of DFS links disappearing from root servers within every 30 minutes. 

Note DFS Links and their associated reparse point might disappear at any time during the runtime of the server.

Cause

This issue occurs because the system time is changed in the middle of the DFS time calculation operation for folder scavenging during the DFS Namespace service initialization process. When the DFS Namespace service starts, it creates reparse points for all the links in the namespace. The service also deletes any reparse points that are in a DFS root share path and do not belong to the namespace. During the service startup and the hourly synchronization, every link of the reparse points is stamped in order to change the time stamps of the reparse points. These time stamps are compared with the startup time of the DFS Namespace service. If the time stamp of a reparse point is earlier than the service startup time, the reparse point is considered an orphan, and is therefore deleted by the service.

When the system time changes before the reparse points are validated, then the changed time of the DFS namespace folders may be earlier than the service startup time. Therefore, the issue that is described in the "Symptoms" section occurs.

Note After you apply this hotfix, the scavenging algorithm for reparse points no longer relies on time stamps for validation.

Resolution

Hotfix information

A supported hotfix is available from Microsoft. However, this hotfix is intended to correct only the problem that is described in this article. Apply this hotfix only to systems that are experiencing the problem described in this article. This hotfix might receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next software update that contains this hotfix.

If the hotfix is available for download, there is a "Hotfix download available" section at the top of this Knowledge Base article. If this section does not appear, contact Microsoft Customer Service and Support to obtain the hotfix.

Note If additional issues occur or if any troubleshooting is required, you might have to create a separate service request. The usual support costs will apply to additional support questions and issues that do not qualify for this specific hotfix. For a complete list of Microsoft Customer Service and Support telephone numbers or to create a separate service request, visit the following Microsoft website: Note The "Hotfix download available" form displays the languages for which the hotfix is available. If you do not see your language, it is because a hotfix is not available for that language.

Prerequisites

To apply this hotfix, you must be running Windows Server 2008 R2 or Windows Server 2008 R2 Service Pack 1 (SP1). Additionally, you must have the DFS Namespace service installed.

For more information about how to obtain a Windows Server 2008 R2 service pack, click the following article number to view the article in the Microsoft Knowledge Base:

976932 Information about Service Pack 1 for Windows 7 and for Windows Server 2008 R2

Registry information

To apply this hotfix, you do not have to make any changes to the registry.

Restart requirement

You must restart the computer after you apply this hotfix.

Hotfix replacement information

This hotfix does not replace a previously released hotfix.
File information

Workaround

To work around this issue, restart the DFS Namespace service on the computer.

Status

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.

More Information

For more information about software update terminology, click the following article number to view the article in the Microsoft Knowledge Base:

824684 Description of the standard terminology that is used to describe Microsoft software updates

Additional file information
Properties

Article ID: 2761922 - Last Review: Nov 12, 2014 - Revision: 1

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