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| This option can be enabled on the Check configuration page |  |
What Are They Useful For?
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- Contacts are notified about the problem (if that's what should be done). Notification intervals are ignored for volatile checks.
- The event handler for the check is run (if one has been defined)
These events normally only occur for checks when they are in a non-OK state and a hard state change has just occurred. In other words, they only happen the first time that a check goes into a non-OK state. If future checks of the check result in the same non-OK state, no hard state change occurs and none of the events mentioned take place again.
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