Downtime shown in the Recovery Alerts and the Alerts History (see Alerts History) is calculated based on the Alert Rule set for the monitor.
That means both in Recovery alerts and Alerts History downtime is calculated as:
– The time difference between the first Problem Alert (sent when the Alert Rule is met), and the Recovery Alert (sent as soon as the Alert Rule is no longer met).
The example below will help you understand this better:
Example: The User has an external monitor “M” running from locations A, B, and C. He has configured the following Alert Rule:
– Alert Rule: Notify the User if M fails 1 time from 2 locations
The flow of events is as follows:
13:55 – The status of M is “OK” from all locations.
14:00 – M fails from location A.
14:05 – M fails from location B. The Problem Alert is triggered (as M is now failed 1 time from 2 locations so the Alert Rule is met) and sent to the User.
14:10 – M fails from location C.
14:15 – M recovers from location C.
14:20 – M recovers from location A. The Recovery Alert is triggered (as M is now in failed state only from 1 location (B), so the Alert Rule is no longer met) and sent to the User.
14:25 – M recovers from location B.
As a result:
- Downtime shown for M both in the Recovery Alert and the Alerts History will be 15 min (between 14:05 and 14:20).
- Location A – downtime is 20 min
- Location B – downtime is 20 min
- Location C – downtime is 5 min