About Alerts

Alerts help you monitor your database. Most alerts notify you of when particular metric thresholds are exceeded. For each alert, you can set critical and warning threshold values. These threshold values are meant to be boundary values that when exceeded, indicate that the system is in an undesirable state. For example, when a tablespace becomes 97 percent full, this can be considered undesirable, and Oracle Database generates a critical alert.

Other alerts correspond to database events such as Snapshot Too Old or Resumable Session suspended. These types of alerts indicate that the event has occurred.

In addition to notification, you can set alerts to perform some action such as running a script. For instance, scripts that shrink tablespace objects can be useful for a Tablespace Usage warning alert.

By default, Oracle Database issues several alerts, including the following:

• Archive Area Used (warning at 80 percent full)

• Broken Job Count and Failed Job Count (warning when goes above 0)

• Current Open Cursors Count (warning when goes above 1200)

• Dump Area Used (warning at 95 percent full)

• Session Limit Usage (warning at 90 percent, critical at 97 percent)

• Tablespace Space Used (warning at 85 percent full, critical at 97 percent full)

You can modify these alerts and others by setting their metrics.

For more information, see "Managing Alerts".