5.8 Defining the Downtime Objective
Downtime is the amount of time measured in days, hours, minutes, and seconds (to the thousandths of a second) that an element remains at a specified condition for a specified time interval. That is, downtime is the total elapsed time during an outage.
If an elements condition is greater than or equal to the threshold condition, then it is considered down or unavailable. Otherwise the element is considered available. The amount of time that an element is scheduled to be unavailable is not factored into the downtime.
When downtime is calculated for an element based on impact to service, only those outages on child elements that impacted the service for the element are considered.
The downtime objective defines an acceptable level of total downtime within a selected interval of time. Downtime is defined by a threshold condition; the default is Critical.
For example, in On times, allow a maximum downtime of 15 minutes within a 2 hour interval that is aligned and a threshold condition of Critical.
Figure 5-5 Downtime Objective with Default Options
To define the Downtime objective, set the following:
Time Category: The time category specifies when to collect data to use to determine the amount of downtime. This time category is associated with a calendar that is specified during the creation of the SLA to which this objective belongs.
Compliance Threshold: The threshold compliance is the maximum amount of downtime that is allowed for the objective to be still in compliance. Designate a whole number of seconds, minutes, or hours.
Outages Ignored: By default, all outages are considered toward downtime.
(Optional) Specify that outages lasting a whole number of seconds, minutes, or hours not be considered part of downtime.
Time Interval: The time period in which to calculate downtime. For more information, see Section 5.4, Understanding Time Intervals.
Threshold Condition: The threshold is the condition at which the objective considers the element to be down or experiencing an outage. That is, the time that the element is at or below this condition is considered downtime calculation.
The default is Critical. This default can be changed.
When an element has a condition of either Unknown or Unmanaged, then it is treated as available or up.
Violation Condition: When the objective is out of compliance, the condition of the objective is Critical. You can change this condition. However, changing this condition has absolutely no impact on the state of the objective at any other time (for example, when it is halfway to the failure state). The state of a failed objective has absolutely no impact on the state of the SLA, which is determined by health scores of objective and not state of objectives.
When an objective is halfway to failure, the state of the objective always defaults to Major. For example, if 5 minutes of downtime is allowed, when the outage reaches 2.5 minutes, the objective state changes to Major.
Activation and Deactivation Dates: (Optional) Indicates when the objective starts and ends. For more information, see Section 5.3, Understanding Activation and Deactivation Dates.