The Nagios web interface allows listing all scheduled downtimes. This page can be accessed by clicking on the Downtime link on the left-hand menu. The following is a screenshot of the page:

The page consists of two pages of all scheduled downtimes, for hosts and services separately. You can delete a downtime by clicking on the trash icon on the right, in the row that describes this particular downtime entry.

Downtimes can be triggered by other downtimes. When a host downtime is scheduled, Nagios automatically adds downtimes for all child hosts.

In order to schedule a downtime, open a host or service information page and use the Schedule downtime for this host or Schedule downtime for this service options. It is also possible to use the downtime page to schedule...