This article discusses the statuses assigned to Kentik Synthetics tests.
Test Status Levels
The results from most synthetic tests are evaluated in three areas (latency, packet loss, and jitter) on a continuous basis to assign the test one of the following statuses for each of those areas:
Healthy: No issues have been found that would significantly impact performance.
Warning: Issues have been found that could significantly impact performance if not addressed.
Critical: Issues have been found that are significantly impacting performance and need immediate attention.
Pending: The test exists but no results are available yet.
Notes:
Each health status (latency, packet loss, and jitter) can be enabled/disabled individually, with a minimum of one enabled status per test (see Health Threshold Controls).
A test’s health status can be evaluated as a whole or per agent (see Status Calculations under Health Settings Tab).
For more about how test data is evaluated for status, see Latency and Jitter Status and Packet Loss Status.
BGP Monitoring, DNS, and Transaction tests do not include the test status levels described above.
Status Time and Scope
Each test defined on the Tests page runs at the configured testing frequency (available frequencies vary depending on test type). This testing frequency is independent of the time range (lookback duration) for which test results may be viewed, which may range from last 5 minutes to the last 30 days. The longer the time range, the wider the time over which data from testing will be aggregated to create a set of "time slice" values. The following examples illustrate how this works for various time ranges:
Last 1 hour: If the time slice is one minute, the latency and jitter values for the current one-minute slice will be compared against the average of the corresponding values for the 15 preceding minutes.
Last 6 hours: If the time slice is 5 minutes, the latency and jitter values for the current five-minute slice will be compared against the average of the corresponding values for the 15 preceding five-minute slices (last 75 minutes).
Last 1 day: If the time slice is 60 minutes (one hour), the latency and jitter values for the current 60-minute slice will be compared against the average of the corresponding values for the 15 preceding 1-hour slices (last 15 hours).
Notes:
The time range for an individual test may be set on its Test Results page. On the Tests page, the time range is always calculated as described for Last 1 Hour above.
The frequency of an individual test is set in the Test Information section of the Test Settings page for that test.
Latency and Jitter Status
For latency or jitter, the status calculation involves comparing the metric’s value in the current time slice to a baseline value representing the average for the prior 15 time slices. The basis of comparison (milliseconds, percentage, standard deviation, etc.) is chosen with the Use setting in the Thresholds control set of the test’s Health Settings Tab.
Assuming the default standard deviation settings, status is indicated as Healthy unless one of the following applies:
Warning: The current value exceeds the baseline by a Kentik-calculated amount, and the difference is between 1.5 and 3 standard deviations.
Critical: The current value exceeds the baseline by a Kentik-calculated amount, and the difference exceeds 3 standard deviations.
Notes:
The default deviation values above can be changed.
Kentik uses a sliding scale to calculate the amounts above so that a large change in terms of standard deviation doesn't trigger a status of Warning or Critical when the amount is not large enough to realistically impact performance.
Packet Loss Status
For packet loss, the status is characterized as Healthy unless one of the following applies:
Warning: The current packet loss value is between 0 and 50 percent.
Critical: The current packet loss value is greater than 50 percent.
Note: The default percentage values above can be changed in the test’s Health Settings Tab.
Overall Status
In many places within our Synthetics UI, the status values for latency, packet loss, and jitter are presented individually; in other places, an overall status is presented. The overall status represents the worst status across the three areas. In other words, if the status of latency and packet loss are Healthy but the status of jitter is Warning, then the overall status will be shown as Warning.