Monitoring the SAP Data
Disk
It is vital to regularly check the space used by the server. If the data file or log file of the database is full, the SAP system will come to a standstill. Although, after the installation of the SAP system, the autogrow option is set and files automatically grow whenever they are full, this still does not guarantee that disks will not run out of space. Checking the amount of free space available on the disk must always be one of the routine tasks performed by a database administrator.

When you look at the amount of free space specified for logs, keep in mind that the data displayed reflects snapshots taken at a specific point in time. Depending on your backup strategy, logs might be backed up and truncated at hourly intervals. As a result, a large amount of free space might be displayed because the log has just been truncated. For more information see Monitoring the SAP Log Disk.
Use the following procedure in the SQL Server Management Studio, to get a quick overview of the current size of the database files and the free space available.
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1. In the SQL Server Management Studio, expand the server and Databases.
2. Right-click the <SAPSID> database and choose Properties, and then View ® Taskpad.
On the right-hand pane, you can see the database size and available space.
Use this procedure to get an overview of the space used by the SAP database over a longer period of time.
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1. Go to the DBACOCKPIT with transaction DBACOCKPIT and navigate to Space ® History® Database Size History.
2. Use the available pushbuttons to change the period for which you want to view space history.