Here is the checklist.
1) Check all WFE and APP servers gac folder that the assambly file of DLC named “DiagnosticLogCompression.dll” has registered.
2) Check Sharepoint Timer Job Service is running and has correct account on every WFE and APP Servers.
3) Check Diagnostic Log Compression feature is installed and enabled on Sharepoint Central Administration Application
CA-> Site Settings -> Manage Site Features and check Diagnostic Log Compression Feature is activated.
4) Check Sharepoint Timer Job Service Identity has enough rights to read/write to destination folder for log copy/move operations.
5) If you are using UNC path check from every WFE and APP server havent any connection problem to reach defined UNC.
6) Monitor from ULS Log via ULS viewer that Compression job is running as expected.
You can download ULS Viewer from this link : http://archive.msdn.microsoft.com/ULSViewer
Job Starting Message:
DLC -> Job: Message:Job Starting
Directory Check Message:
DLC -> Job: Message:Directory is OK! : \\YOUR_NETWORK_PATH
The Log file is inuse message:
DLC -> Job: Message:File in usage:C:\Program Files\Common Files\Microsoft Shared\Web Server
Extensions\14\LOGS\POSTPOINT2010-20110610-1927.log
Several processed log file message:
DLC -> Job: Message:Processing -> C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\14\LOGS\POSTPOINT2010-20110606-1744.log
…
Finish message:
DLC -> Job: Message:Job completed successfully
7) If you do any update or manuel installation don’t forget to reset Sharepoint Timer job Service on updated server. For example getting Error of in ULS Log:
06/10/2011 19:36:03.45 OWSTIMER.EXE (0x21BC) 0x2018 SharePoint Foundation Topology umbo High The type DiagnosticLogsHelper.JobLogCompress, DiagnosticLogCompression, Version=1.0.0.0, Culture=neutral, PublicKeyToken=c1b6bc305019fff6 could not be found in its specified assembly. Scanning all assemblies that have been loaded in the current app domain.
end of list.
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