NTP (Network Time Protocol) is designed to mitigate network latency by keeping computer system clocks in sync. There are various NTP servers located around the world which systems can connect to to keep their clocks within a few milliseconds of real time. The Catchpoint NTP Test monitors the availability of a single NTP server.
This type of Test is typically run on Enterprise nodes to verify connectivity to their configured NTP Servers.
NTP Test Properties | |
|---|---|
| Name | A name used to identify this test. |
| Description | Optional additional information about the test |
| Test Location | The IP Address or hostname of the NTP server to be tested. |
| Location | The Product/Folder location of this test (read only) |
| Status | Determines whether this test is current Active or Inactive |
Supported Metrics | |
|---|---|
| # Purged Runs | The number of test runs manually excluded from calculation for purposes of SLA accuracy. |
| # Runs | Total number of test runs for the defined time period. |
| # Test Errors | The total number of test runs that failed. This is the sum of all of the following types of test failures:
|
| % Adjusted Availability | Ignoring any purged runs, the percentage of test runs where the server was reached and the test was completed (i.e. there was not a Test Error.) |
| % Availability | The percentage of test runs where the server was reached and the test was completed (i.e. there was not a Test Error.) Availability is calculated as: (# Test Runs - # Test Errors) / # Test Runs |
| % Downtime | The percentage of test runs where the server was unavailable, unreachable, or otherwise failed (i.e. there was a Test Error.) Downtime is calculated as: # Test Errors / # Test Runs |
| % Ping Packet Loss | The percentage of pings packets sent which did not receive a response. Calculated as: (# packets received / # packets sent) * 100 |
| DNS (ms) | The time it took to resolve the domain name to an IP address. |
| Negative Offset (ms) | The estimated amount of time that the client clock is ahead the server |
| NTP round-trip delay (ms) | The total amount of time that the NTP request and response were in transit between the node and the server. |
| Ping Round Trip (ms) | Average time between sending a ping packet and receiving a response. |
| Positive Offset (ms) | The estimated amount of time that the client clock is behind the server. |
| Response (ms) | The total time from the initial request until receiving the last packet of response data. It is the sum of DNS + Connect + ssl + Send + Wait + Load for all elements. |
| Root Delay (ms) | The estimated delay between the local system clock and the root clock. |
| Root Dispersion (ms) | The estimated error in the local system clock since it was last synchronized with the upstream clock. |
| Signal Quality | Measures the quality of the WLAN connection in terms of data transfer speed. It indicates what percent of the available network are you using to move data (upload / download). 99% is as good as it gets in terms of signal quality. |
| Signal Strength (dBm) | This number represents the power the clients device is receiving from the Access Point / Wi-Fi router. A number of -30 dBm indicates excellent while a number of -70dBm indicates very poor signal strength. |
| Test Time (ms) | One cohesive metric that applies to all test types and indicates the total duration of the test run. Test Time is equivalent to Response, Test Response (Transaction and web tests) and ping RTT (Trace Route tests), and is used when calculating Apdex. Test Time is not available for Request, Host, or Zone charting. |