The startup process stops responding on a Windows Server 2008 R2-based computer that has many processors and Fibre Channel adapters installed

Applies to: Windows Server 2008 R2 DatacenterWindows Server 2008 R2 EnterpriseWindows Server 2008 R2 for Itanium-Based Systems

Symptoms


Assume that you have a Windows Server 2008 R2-based computer that has more than 64 processors and has some Fibre Channel adapters installed that are connected to external storage devices. In this situation, the computer randomly stops responding during the startup process.

For example, this issue occurs on a Windows Server 2008 R2-based computer that has 256 processors and 16 Fibre Channel adapters installed that are connected to more than 140 logical unit numbers (LUNs).

Note This issue occurs more frequently when the computer has a larger number of processors or a larger number of Fibre Channel adapters installed.

Cause


This issue occurs because the execution of code instructions in the Storport.sys driver is not completed in the expected order and this may cause completed I/O to not be flushed.

Resolution


Hotfix information

A supported hotfix is available from Microsoft. However, this hotfix is intended to correct only the problem that 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 one of the following operating systems:
  • Windows Server 2008 R2
  • Windows Server 2008 R2 Service Pack 1 (SP1)
For more information about how to obtain a Windows 7 or 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 use the hotfix in this package, 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

The global version of this hotfix installs files that have the attributes that are listed in the following tables. The dates and the times for these files are listed in Coordinated Universal Time (UTC). The dates and the times for these files on your local computer are displayed in your local time together with your current daylight saving time (DST) bias. Additionally, the dates and the times may change when you perform certain operations on the files.
Windows Server 2008 R2 file information notes
Important Windows 7 hotfixes and Windows Server 2008 R2 hotfixes are included in the same packages. However, hotfixes on the Hotfix Request page are listed under both operating systems. To request the hotfix package that applies to one or both operating systems, select the hotfix that is listed under "Windows 7/Windows Server 2008 R2" on the page. Always refer to the "Applies To" section in articles to determine the actual operating system that each hotfix applies to.
  • The files that apply to a specific product, SR_Level (RTM, SPn), and service branch (LDR, GDR) can be identified by examining the file version numbers as shown in the following table.
    VersionProductSR_LevelService branch
    6.1.760
    0.
    21xxx
    Windows Server 2008 R2RTMLDR
    6.1.760
    1.
    21xxx
    Windows Server 2008 R2SP1LDR
  • The MANIFEST files (.manifest) and the MUM files (.mum) that are installed for each environment are listed separately in the "Additional file information for Windows Server 2008 R2" section. MUM and MANIFEST files, and the associated security catalog (.cat) files, are extremely important to maintain the state of the updated components. The security catalog files, for which the attributes are not listed, are signed with a Microsoft digital signature.
For all supported x64-based versions of Windows Server 2008 R2
File nameFile versionFile sizeDateTimePlatform
Storport.sys6.1.7600.21101188,78401-Dec-201106:37x64
Storport.sys6.1.7601.21870191,34401-Dec-201106:23x64
For all supported IA-64–based versions of Windows Server 2008 R2
File nameFile versionFile sizeDateTimePlatform
Storport.sys6.1.7600.21101430,96001-Dec-201105:26IA-64
Storport.sys6.1.7601.21870430,96001-Dec-201105:26IA-64

Workaround


To work around this issue, use one of the following methods
  • Disconnect external storage devices before you start the computer.
  • Disable the installed Fibre Channel adapters.
  • Reduce the number of processors to 64 or fewer.

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

Additional file information for Windows Server 2008 R2

Additional files for all supported x64-based versions of Windows Server 2008 R2
File nameAmd64_27276ab8d3a7779985aac4bfd8e03589_31bf3856ad364e35_6.1.7601.21870_none_37770a7508b87c54.manifest
File versionNot applicable
File size700
Date (UTC)01-Dec-2011
Time (UTC)17:32
PlatformNot applicable
File nameAmd64_c9fb56163e20aa8b83a530ad25fece72_31bf3856ad364e35_6.1.7600.21101_none_4d45f718e405467e.manifest
File versionNot applicable
File size700
Date (UTC)01-Dec-2011
Time (UTC)17:32
PlatformNot applicable
File nameAmd64_microsoft-windows-storport_31bf3856ad364e35_6.1.7600.21101_none_844d3ed962c0698c.manifest
File versionNot applicable
File size15,727
Date (UTC)01-Dec-2011
Time (UTC)07:01
PlatformNot applicable
File nameAmd64_microsoft-windows-storport_31bf3856ad364e35_6.1.7601.21870_none_85e713ff60204c76.manifest
File versionNot applicable
File size15,727
Date (UTC)01-Dec-2011
Time (UTC)06:49
PlatformNot applicable
File nameUpdate.mum
File versionNot applicable
File size3,215
Date (UTC)01-Dec-2011
Time (UTC)17:32
PlatformNot applicable
Additional files for all supported IA-64–based versions of Windows Server 2008 R2
File nameIa64_33e42d8356ffb54b4a66c0aa43c7a156_31bf3856ad364e35_6.1.7600.21101_none_b838ab9d3f3a2596.manifest
File versionNot applicable
File size698
Date (UTC)01-Dec-2011
Time (UTC)17:32
PlatformNot applicable
File nameIa64_b5f130eea12b2cc2306b06af30ba0bd2_31bf3856ad364e35_6.1.7601.21870_none_0a00b43ed825ca51.manifest
File versionNot applicable
File size698
Date (UTC)01-Dec-2011
Time (UTC)17:32
PlatformNot applicable
File nameIa64_microsoft-windows-storport_31bf3856ad364e35_6.1.7600.21101_none_2830474baa610152.manifest
File versionNot applicable
File size15,726
Date (UTC)01-Dec-2011
Time (UTC)06:54
PlatformNot applicable
File nameIa64_microsoft-windows-storport_31bf3856ad364e35_6.1.7601.21870_none_29ca1c71a7c0e43c.manifest
File versionNot applicable
File size15,726
Date (UTC)01-Dec-2011
Time (UTC)06:42
PlatformNot applicable
File nameUpdate.mum
File versionNot applicable
File size1,947
Date (UTC)01-Dec-2011
Time (UTC)17:32
PlatformNot applicable