SharePoint Logging

1. Gives the report for site and site collection usage information.

2. Unified logging service ULS logs - we can write custom logs by
SPDiagnosticsService diagSvc = SPDiagnosticsService.Local;
                diagSvc.WriteTrace(0,
                                                        new SPDiagnosticsCategory("Sowmyan's category", TraceSeverity.Monitorable, EventSeverity.Error),
                                                        TraceSeverity.Monitorable,
                                                        "Writing to the ULS log:  {0}",
                                                        new object[] { "SharePoint 2010 rocks!" });

3. Event logs - we can write custom logs by
 System.Diagnostics.EventLog.WriteEntry("Rahul", "Testing");

4. Store all logging information in new database from all the WFEs. So all logging info at one place.

5. customerrormode = off and CallStack=true to see the error call stack on page.

6. Custom applicaton page: there is new SPWebApplicaton.SPCustomPage enumerator which will replace OOB application page with custom page

webApp.UpdateMappedPage(SPWebApplication.SPCustomPage.AccessDenied,
          "/_layouts/CustomErrorPages/AccessDenied.aspx")

7. Develepor dashboard to view report of the page.