File group is running out of space

Monitor : DB File Space (rollup)

SQL MP Version : 6.3.173.1

SCOM 2007 R2 with CU2

Issue : We are receiving alert File group is running out of space from monitor DB File Space (rollup) for file groups which do not exist on the SQL server.

Lately we are receiving an alert, File group is running out of space, every week from monitor DB File Space (rollup) for file group on a  SQL server, and when the SQL Admin checks the SQL database, no such file group exists. This is a SharePoint database, where a weekly job runs and creates a new file group every week. It probably also goes ahead and deletes the oldest file group. The alert we receive is for the oldest file group. Ideally we should be receiving an alert saying, File group is not available, however we receive an alert saying File group is running out of space.

Also I see that the object discovery for database is set to 4 hours, however I do not see an object discovery for file group. So I understand that when the database is discovered, corresponding file groups are also discovered. So ideally if a new file group has been added it should be discovered and any file group which no longer exist should be discarded during the object discovery. However, after the object discovery is run, the non-existing file group is discarded, but an alert saying File group is running out of space for the non-existing file group is logged.

SQL Admins also confirm that there is enough space within the drive and the filegroup is set as unrestricted. They alsocheck Windows logs and SQL error logs, and there are no error messages available related to file group.

Kindly suggest.

Thanks, Harry :-)