MustGather setup of error reporting dump tools for Microsoft Windows

• Setup for Windows Server 2008 and newer versions
• Setup for Windows Server 2003 and earlier versions

Setup for Windows Server 2008 and newer versions

The Dr.Watson tool is no longer supplied with Microsoft Windows starting with the Microsoft Vista version of Windows. On the newer versions of Microsoft Windows, you will need to configure 'LocalDumps' on the system in order to generate the dump files needed for problem analysis and save them locally on the server. This setup step must be performed prior to recreating the problem scenario.

The LocalDumps configurations can be made to apply globally for all applications on the system or for specific applications. The instructions below will configure dumps specifically for the 'IBM HTTP Server' (IHS) application. If you already have global LocalDumps settings, those settings will continue to be in effect for other applications, but will be overridden for IHS by the settings below.

1. Logon to the server system as Administrator or a user that has administrator privileges.
2. Create a directory into which any generated dump files are to be placed.
   'C:\crashdumps' for example. (Make sure all users can write to this directory.)
3. Add the needed 'LocalDumps' entries into the Windows registry.
   The entries can be added to the registry by either of two techniques. They can be added by using the Windows Registry Editor (regedit) if you are comfortable using that tool. Alternatively, 'reg' commands have been provided which can be copied and executed at a Windows command prompt to add the entries. Both methods are described below.

   Update the registry using 'reg' commands

   To use this technique, you should open an Administrator Command prompt window with elevated privileges.
   This can be done by Rt-clicking a 'Command Prompt' icon (ex: under 'Start->All Programs->Accessories') and selecting 'Run as administrator'.

   Copy and paste each of the following commands into the Administrator command prompt window, and then press Enter to execute the command.
   You should see a message like "The operation completed successfully." after the completion of each command:
   (Note: The third command assumes you created a dump directory named 'C:\crashdumps'. If you are using a different directory then adjust that value as needed.)
   
   reg add "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\Windows Error Reporting\LocalDumps" /f
reg add "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\Windows Error Reporting\LocalDumps\httpd.exe" /f
reg add "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\Windows Error Reporting\LocalDumps\httpd.exe" /v DumpFolder /t REG_EXPAND_SZ /d "C:\crashdumps" /f
reg add "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\Windows Error Reporting\LocalDumps\httpd.exe" /v DumpType /t REG_DWORD /d "1" /f

   Update the registry using the Windows Registry Editor (regedit)

   • Start regedit
   • Navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\Windows Error Reporting
   • Create a 'LocalDumps' key under 'Windows Error Reporting' if it doesn't already exist.
     To create the key, Rt-click 'Windows Error Reporting' and select 'New->Key', then enter "LocalDumps" as the key name.
   • Create a 'httpd.exe' key under 'LocalDumps' if it doesn't already exist.
     To create the key, Rt-click 'LocalDumps' and select 'New->Key', then enter "httpd.exe" as the key name.
   • Create a 'DumpFolder' key under 'httpd.exe' with a value of 'C:\crashdumps' (or whatever directory you created to store the dump files into)
     To create the key:
     -Rt-click 'httpd.exe' and select 'New->Expandable String Value'
     -Enter 'DumpFolder' as the key name
     -Double-click the new key name to provide its value and enter the pathname of the directory to be used to store the dump files (ex: C:\crashdumps)
   • Create a 'DumpType' key under 'httpd.exe' with a value of '1' (which indicates to generate a 'Minidump' dump file)
     To create the key:
     -Rt-click 'httpd.exe' and select 'New->DWORD (32 bit) Value'
     -Enter 'DumpType' as the key name
     -Double-click the new key name to provide its value. Select the 'Decimal' option for 'Base', then enter '1' for 'Value data'.

   Upon completion of adding the entries into the Windows registry, they would look like the following if viewed used the Windows Registry Editor (regedit):

   

To configure for a 'Full dump' if requested by IBM support

To obtain a 'Full dump' dump file, you will need to set the value of the 'DumpType' entry to '2'. You can either use regedit to manually modify this entry (see above info for the location), or use the following technique to execute a 'reg' command at a Windows command prompt to make the update:

• Open an Administrator Command prompt window with elevated privileges.
  This can be done by Rt-clicking a 'Command Prompt' icon (ex: under 'Start->All Programs->Accessories') and selecting 'Run as administrator'.
• Copy and paste the following command into the Administrator command prompt window, and then press Enter to execute the command:
  reg add "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\Windows Error Reporting\LocalDumps\httpd.exe" /v DumpType /t REG_DWORD /d "2" /f
  You should see a message like "The operation completed successfully." after completion of the command.

To adjust the max number of dump files if requested by IBM support

By default, up to 10 dump files can be created at which point the oldest dump files will start being overwritten as new ones are created. If for some reason, there is a need to gather more than 10 dump files, the count can be adjusted as follows. Note that the provided command will double the dump count to 20. The '20' in the command can be adjusted to another value as requested or needed.

• Open an Administrator Command prompt window with elevated privileges.
  This can be done by Rt-clicking a 'Command Prompt' icon (ex: under 'Start->All Programs->Accessories') and selecting 'Run as administrator'.
• Copy and paste the following command into the Administrator command prompt window, and then press Enter to execute the command
  reg add "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\Windows Error Reporting\LocalDumps\httpd.exe" /v DumpCount /t REG_DWORD /d "20" /f
  You should see a message like "The operation completed successfully." after completion of the command.

Setup for Windows Server 2003 and earlier versions

The Dr.Watson tool supplied with Windows must be configured to save information about program crashes and hangs. This setup step must be performed prior to recreating the problem scenario.

1. Start DRWTSN32.EXE from a command prompt. The Dr.Watson configuration dialog will be displayed and will look similar to the following:

   

2. Set the Log file and Crash dump paths to the desired locations. Make a note of these values for later use.
   After a crash has occurred, the drwtsn32.log and user.dmp files will be retrieved from those locations.
3. Ensure that 'Number of Instructions' is at least 10.
4. Ensure that 'Number of Errors to Save' is at least 10.
5. Select 'Full' for the 'Crash Dump Type' option.
   (This option will not appear for Windows 2000)
6. Enable the following options (by selecting the associated checkboxes):
   • Dump Symbol table
   • Dump All Thread Contexts
   • Append to Existing Log File
   • Create Crash Dump File
7. We recommend that the following option be disabled so that IBM HTTP Server recovers as quickly as possible after a crash:
   • Visual Notification
8. Click 'OK' to save these settings.
9. Enable Dr.Watson as your default Windows debugger by entering the following at a command prompt:
   drwtsn32 -i
   (This will make the necessary changes in the Windows registry.)

Related information

• 'Collecting User-Mode Dumps' (Windows Vista/7/2008 and newer)
• 'Dr. Watson overview'