Under which condition does a failure event occur in the event inspector?

A failure event occurs in the event inspector under the condition where a property is out of sync and the changes failed. This scenario indicates that the desired state of the configuration, as defined in Puppet, could not be achieved, often due to issues such as incorrect configurations, lack of required permissions, or unavailable resources.

When Puppet applies configurations, it reports the state of resources and whether it could bring them into the desired state. If a resource is not in the correct state (i.e., out of sync) and an attempt to rectify this fails, it leads to a failure event being logged. This helps users understand that while a change was attempted, it did not succeed, highlighting areas that need attention for resolution.

The other scenarios do not qualify as failure events because they reflect situations where changes were successfully made or where requirements were met without issue. A valid and successful application of a resource or property indicates that everything functioned as intended, and thus would not trigger failure events in the inspector.