AD CS database CRL table

The Microsoft AD CS database has a specific table for Certificate Revocation Lists (CRLs). By default, CRLs are kept in the database for some time after expiration and then they are deleted, so that the CRL table usually contains a reduced number of entries and does not grow as time goes by.

This default behaviour can be controlled via one of the CRLFlags in the AD CS configuration, called CRLF_DELETE_EXPIRED_CRLS.


When the flag is set expired CRLs will regularly be deleted from the CRL table in the database, if the flag is unset CRLs will be kept in the database.

To modify the flag the usual commands can be used. To set the flag (default after deployment):

certutil -setreg CA\CRLFlags +CRLF_DELETE_EXPIRED_CRLS

And to unset the flag:

certutil -setreg CA\CRLFlags -CRLF_DELETE_EXPIRED_CRLS

The AD CS service must be restarted for those configuration changes to take effect.


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