Monitoring the Health and Status of Your Infrastructure : Health degradation root cause
  
Health degradation root cause
You can rapidly drill down to the root cause of group, site, device, and interface health degradation by clicking through to the degraded object’s At a Glance page and clicking the Health and Interface Health indicator icons in the information ribbon. For a group or site, you can immediately determine the degraded assets and then drill into the specific asset.
For a device or interface, you can immediately determine the metric causing the degradation.