Why does my Image Map dashboard report "No Data" when it was previously working?
When creating an Image panel in a dashboard, the group and the number in the Limit field of the Metric > Object Type play a huge role when configuring the Image Map properties
By default the Object Type Limit field is set to 50
If there are interfaces, CPUs, devices or other entities that belong to the object or the Group being used are in excess of that number then this can cause issues.
The Limit number should cover the number of entities in the group.
By default you will only be able to select from 50 interfaces - for example - when configuring the Image Map properties and the interface you want may not be listed.
Even if the interfaces required are listed, and the map panel is configured exaclty as needed, when placing additional devices or interfaces in the group, either by auto-grouping or manually, the entity selected - interfaces - in the example (even if previously selected and working) may now fall outside of the limit, causing the panel to report No Data