User Experience Insight sensors run synthetic tests one at a time in a continuous round-robin sequence.
There are two types of issues observed in the dashboard that generate notifications:
Threshold Violations: If the sensor runs a test and gets a successful result, the test's measured value is reported to the dashboard. Threshold issues arise when measured data samples exceed a defined threshold. These thresholds are configurable by a dashboard administrator. Example issues: High DHCP response time, High DNS lookup time.
For threshold violations, you can check for any underlying wired or wireless issues on the network, or take an on-demand packet capture on the sensor to gain more insights. By analyzing historical sensor test results, you can adjust the settings to fine-tune the thresholds. Make sure to adjust the time period and not just the value to include more measurements in the calculations.
Test Failures: If the sensor runs a test and does not get a successful result, it will attempt to diagnose the cause of the failure in automated triage mode. Triage mode will run a set of predefined troubleshooting tests to get the root cause of the test failure. Example issues: Gateway is unreachable, Primary DNS Failing, No Response from DHCP Server.
For example, by using the issue triage one can easily determine if a certain website is only failing on the wireless network or wired network, or both by comparing test results performed on both networks, step by step root cause analysis by issue triage is shown below. You will also get a packet capture for issue triage if you have set up the sensor with PCAP Full.