The disk space usage monitor provides information about the amount of usable disk space available for server components. It also provides the ability to generate administrative alerts, as well as take action if the amount of usable space drops below the defined thresholds.

Disk space monitoring excludes disk locations that do not have server components registered. However, other disk locations may still impact server performance, such as the operating system disk, if it becomes full. When relevant to the server, these locations include the server root, the location of the config directory, the location of every log file, all JE backend directories, the location of the changelog, the location of the replication environment database, and the location of any server extension that registers itself with the DiskSpaceConsumer interface.

All values must be specified as absolute values or as percentages. A mix of absolute values and percentages cannot be used. The following thresholds are available:

Low space warning
This threshold defines either a percentage or an absolute amount of usable space. If the amount of usable space drops below this threshold, the server generates an administrative alert. It generates alerts at regular intervals, based on configuration settings, until the amount of usable space is increased, or as the amount of usable space is further reduced.
Low space error
This threshold is also defined as either a percentage or an absolute size. Once the amount of usable space drops below this threshold, the server will generate an alert notification and will begin rejecting all operations requested by nonroot users with "UNAVAILABLE" results. Once the server enters this mode, some action must be taken before the server will resume normal operations. This threshold must be less than or equal to the low space warning threshold. If they are equal, the server will begin rejecting requests from non-root users immediately upon detecting low usable disk space.
Out of space error
This threshold can also be defined as a percentage or an absolute size. Once the amount of usable space drops below this threshold, the server will generate a final administrative alert and will shut itself down. This threshold must be less than or equal to the low space error threshold. If they are equal, the server will shut itself down rather than rejecting requests from non-root users.