What the Snapshot copy reserve is

The Snapshot copy reserve sets a specific percent of the disk space for Snapshot copies. By default, the Snapshot copy reserve is 5 percent of the disk space. The Snapshot copy reserve can be used only by Snapshot copies, not by the active file system.

If the active file system runs out of disk space, any disk space still remaining in the Snapshot copy reserve is not available for use by the active file system.

Note: Although the active file system cannot consume disk space reserved for Snapshot copies, Snapshot copies can exceed the Snapshot copy reserve and consume disk space normally available to the active file system.

Managing the Snapshot copy reserve involves the following tasks:

•	Ensuring that enough disk space is set aside for Snapshot copies so that they do not consume active file system space

•	Keeping disk space consumed by Snapshot copies below the Snapshot copy reserve

•	Ensuring that the Snapshot copy reserve is not so large that it wastes space that could be used by the active file system