Hello.
There is no built-in support to show a Treemap that filters sensors by state, in some case with knowledge of HTML and CSS it is possible to create customized map objects, see this article as an example:
How can I use a status icon of a device in Maps which only considers specific sensors?
But, there is a built-in object that supports what you want, please check the Alarms, Warning Sensors and Down Sensors* objects under Data Tables within the map editor. Those objects also allow some documented modifications:
Can you re-order or remove columns in sensor lists displayed in maps?
About adding specific devices to the Treemap object, that is currently not possible, if you use groups for deploying your devices between PRTG, you can use Treemap objects for the groups, but you cant create a Treemap that shows devices from various groups. That is possible using libraries and the sunburst though.
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