MustGather information for web server hangs or high CPU conditions (Windows)

System preparation

Dr. Watson

The Dr. Watson tool supplied with Windows must be configured to save the proper information. This setup step must be performed prior to saving the hang documentation.

  1. Start DRWTSN32.EXE from the Command Prompt. The Dr. Watson configuration dialog will look similar to the following:
  2. Make a note of the paths of the log file and crash dumps. After Dr. Watson is used later to save information about the hang, files will be retrieved from those locations.
  3. Enable the following options:
  4. We recommend that the following option be disabled so that IBM HTTP Server recovers as quickly as possible after a crash:
  5. Ensure that Number of Instructions is at least 10.
  6. Ensure that Number of Errors to Save is at least 10.
  7. If your version of Dr. Watson has the capability to select Crash Dump Type, then select Full.

AFPA

AFPA must be disabled and IBM HTTP Server restarted in order to collect some of the information below. You must be aware of whether or not AFPA is enabled in the web server configuration file before gathering the hang information. We recommend that AFPA be disabled in advance if the hang is reproducible so that the best set of information is available for analysis.

Obtaining information at the time of the hang

These steps must be performed at the time of the hang

  1. Task Manager information
  2. Web server state

    You must skip this step if AFPA is enabled.

    Note: On Win2000, this step will terminate the IBM HTTP Server child process when it completes. But this information is critical for determining the cause of the hang.

    Run DRWTSN32.EXE -p CHILDPID to create Dr. Watson log and crash files representing the current state of the web server. Replace CHILDPID with the IHS child process PID, as found in the previous step from the Task Manager display.

    If a dialog box appears stating that an error log is being created, don't press Cancel. Instead, wait for the text of the button to change to OK. Then press OK.

    The Dr. Watson files can now be found in the locations configured in the DRWTSN32.EXE program, as displayed above under System preparation. Example:

    C:\Documents and Settings\All Users\Documents\DrWatson>dir
     Volume in drive C is C_Drive
     Volume Serial Number is 98E7-6D3C
    
     Directory of C:\Documents and Settings\All Users\Documents\DrWatson
    
    08/05/2003  09:32a                .
    08/05/2003  09:32a                ..
    04/05/2005  03:48p           1,118,951 drwtsn32.log
    04/05/2005  03:49p          12,969,444 user.dmp
                   2 File(s)     14,088,395 bytes
                   2 Dir(s)  18,162,450,432 bytes free
    

    The files drwtsn32.log and user.dmp are the files to save.

  3. server status report

    From a web browser, request http://www.example.com/server-status/?showmodule from a web browser. (Replace www.example.com with your web server address.) If the web server is completely hung, it may not respond. Otherwise, save the server status report to a file.

  4. TCP connection information

    Run netstat -an > netstat.txt to save TCP connection information.

  5. network configuration

    Run ipconfig /all >ipconfig.txt to save information about the network configuration.

  6. IBM HTTP Server version

    Type one of the following commands to save the full version information to a file:

  7. web server configuration file

    The default file is

    install_root\conf\httpd.conf
    
  8. web server error log

    The default file is

    install_root\logs\error.log
    

    The configuration file may have been changed to specify a different error log.

  9. WebSphere plug-in trace file

    The actual location is specified in plugin-cfg.xml.

    Example:

    c:\WebSphere\AppServer\logs\native.log
    
  10. Windows system information

    Run Start/Programs/Accessories/System Tools/System Information and export the information to a text file:

Recap of information to send to IBM support:

  1. Task manager information, as saved to taskmgr.doc or taskmgr.rtf
  2. If AFPA is disabled: Web server state, as represented in the Dr. Watson log and crash files
  3. server status report, if it could be loaded
  4. TCP connection information, as saved to netstat.txt
  5. network configuration, as saved to ipconfig.txt
  6. IBM HTTP Server version, as saved to ihs_version.txt
  7. web server configuration file
  8. web server error log
  9. WebSphere plug-in trace file
  10. Windows system information, as exported by the System Information program
Instructions to send diagnostic information to IBM support.