Exchange Server Cookbook

6.15. Controlling the Online Maintenance Process

Problem

You want to change the schedule for Exchange Server's scheduled maintenance processes.

Solution

Using a graphical user interface

1. Launch the Exchange System Manager (Exchange System Manager.msc).

2. In the left pane, expand the appropriate Administrative Groups container, and then expand the Servers container.

3. Locate the public folder or mailbox store for which you wish to control maintenance intervals.

4. Right-click the store object and select Properties.

5. Select the Database tab.

6. Select one of the predefined Maintenance Intervals or click Customize to select your own schedule.

7. Click OK.

Discussion

As with most other databases, the ESE holds on to space once it's allocated and reuses it internally instead of returning it to the filesystem. For example, if you create 50 10 MB Word documents and delete 20 of them, you'll regain 200 MB (20 * 10) of space. If your Exchange stores grow to 24 GB and you delete 1.5 GB worth of mailbox data, the stores will still take up 24 GB on disk, but Exchange will be able to recycle the 1.5 GB of free space within the database. The Exchange databases are like a balloon with a one-way valve attached—you can blow it up bigger and bigger, but it doesn't normally get any smaller unless you do something purposeful to let some air out. Online maintenance performs several tasks to optimize the ways in which this whitespace is reused. These tasks include:

Defragmentation

Over time, your Exchange database files will ...