How to write to windows event logs from determinations-server under IIS

Question

This is just an FYI technical bit of information I wish someone had shared with me before I started trying to write OPA errors to the windows event log... Most problems writing to the windows event log from log4net occur because of permissions. Some problems are because determinations-server does not have permissions to create some registry entries. Some problems cannot be resolved unless specific registry entry permissions are actually changed. We had very little consistency with the needed changes across our servers, but some combination of the following would always get the logging to the windows event log working.
To see log4net errors as log4net attempts to utilize the windows event log, temporarily add the following to the web.config:
<appSettings>
<!-- uncomment the following line to send diagnostic messages about the log configuration file to the debug trace.
Debug trace can be seen when attached to IIS in a debugger, or it can be redirected to a file, see
http://logging.apache.org/log4net/release/faq.html in the section "How do I enable log4net internal debugging?" -->
<add key="log4net.Internal.Debug" value="true"/>
</appSettings>
<system.diagnostics>
<trace autoflush="true">
<listeners>
<add
name="textWriterTraceListener"
type="System.Diagnostics.TextWriterTraceListener"
initializeData="logs/InfoDSLog.txt" />
</listeners>
</trace>
</system.diagnostics>
To add an appender for the windows event viewer, try the following in the log4net.xml:
<appender name="EventLogAppender" type="log4net.Appender.EventLogAppender" >
<param name="ApplicationName" value="OPA" />
<param name="LogName" value="OPA" />
<param name="Threshold" value="all" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date [%thread] %-5level %logger [%property{NDC}] - %message%newline" />
</layout>
<filter type="log4net.Filter.LevelRangeFilter">
<levelMin value="WARN" />
<levelMax value="FATAL" />
</filter>
</appender>
<root>
<level value="warn"/>
<appender-ref ref="EventLogAppender"/>
</root>
To put the OPA logs under the Application Event Log group, try this:
Create an event source under the Application event log in Registry Editor. To do this, follow these steps:
1.     Click Start, and then click Run.
2.     In the Open text box, type regedit.
3.     Locate the following registry subkey:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Eventlog\Application
4.     Right-click the Application subkey, point to New, and then click Key.
5.     Type OPA for the key name.
6.     Close Registry Editor.
To put the OPA logs under a custom OPA Event Log group (as in the demo appender above), try this:
Create an event log in Registry Editor. To do this, follow these steps:
1.     Click Start, and then click Run.
2.     In the Open text box, type regedit.
3.     Locate the following registry subkey:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Eventlog
4.     Right-click the eventlog subkey, point to New, and then click Key.
5.     Type OPA for the key name.
6.     Right-click the new OPA key and add a new DWORD called "MaxSize" and set it to "1400000" which is about 20 Meg in order to keep the log file from getting too large.
7.     The next steps either help or sometimes cause an error, but you can try these next few steps... If you get an error about a source already existing, then you can delete the key.
8.     Right-click the OPA subkey, point to New, and then click Key.
9.     Type OPA for the key name.
10.     Close Registry Editor.
You might need to change permissions so OPA can write to the event log in Registry Editor.  If you get permission errors, try following these steps:
1.     Click Start, and then click Run.
2.     In the Open text box, type regedit.
3.     Locate the following registry subkey:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Eventlog
4.     Right-click the EventLog key, select Permissions.
5.     In the dialog that pops up, click Add...
6.     Click Advanced...
7.     Click Locations... and select the current machine by name.
8.     Click Find Now
9.     Select both the Network user and IIS_IUSERS user and click OK and OK again. (We never did figure out which of those two users was the one that fixed our permission problem.)
10.     Change the Network user to have Full Control
11.     Click Apply and OK
To verify OPA Logging to the windows event logs from Determinations-Server:
Go to the IIS determinations-server application within Server Manager.
Under Manage Application -> Browse Application click the http link to pull up the local "Available Services" web page that show the wsdl endpoints.
Select the /determinations-server/server/soap.asmx?wsdl link
Go to the URL and remove the "?wsdl" from the end of the url and refresh. This will throw the following error into the logs:
ERROR Oracle.Determinations.Server.DSServlet [(null)] - Invalid get request: /determinations-server/server/soap.asmx
That error should show up in the windows event log, OR you can get a message explaining why security stopped you in "logs/InfoDSLog.txt" if you used the web.config settings from above.
http://msdn.microsoft.com/en-us/library/windows/desktop/aa363648(v=vs.85).aspx
Edited by: Paul Fowler on Feb 21, 2013 9:45 AM

Answer 1

Thanks for sharing this information Paul.