A. Active Directory (AD) can record sequential or circular logs. The default logging method is sequential. Sequential log files aren’t overwritten with new data. These files grow until they reach a specified size. After all the transactions in a log file are committed to the database, the log file is unnecessary. AD’s garbage-collection process deletes unnecessary log files every 12 hours by default. If your server doesn’t stay up longer than 12 hours between reboots, AD can’t clean up old log files. Eventually, the files will use all your available disk space.

Circular logs overwrite transactions at specific intervals. Some administrators prefer circular logging because this method helps minimize the amount of logged data the physical disk must store. To enable circular logging, you need to edit the Registry.

1. Start regedt32.
2. Go to the HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\NTDS\Parameters Registry entry.
3. If the value CircularLogging doesn’t exist, select New, String value from the Edit menu and enter
   

   CircularLogging

4. Double-click CircularLogging, and set the value to 1 to enable circular logging. (Setting the value to 0 disables circular logging and enables sequential log files).
5. Close the Registry editor.
6. Reboot the machine to restart the Directory Service (DS) and make the change effective.