Understand the Overview bar
The Overview Bar summarizes your environment in a compact space. If your view is currently filtered, the filtered objects will be displayed above the Overview Bar, as shown. Individual filtered objects
The doughnut chart in the Overview section graphically displays the ratio of objects to one another in all possible states using indicative colored slices. The total number of objects in your environment is also displayed.
Objects under the Issues header are parsed and enumerated according to status. Objects shown here will be in one of the following distressed states: Down, Critical, Warning, Unknown and Unreachable. An icon and count will only appear if at least one object is currently in that state.