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In the visualization, a group displays the highest status level of the monitor items it contains. As such, if a group contains 4 monitor items that all have the status “Ok”, then the group also has the status “Ok”. If one of the items changes to status “Error”, the group changes to “Error” as well. If another item changes status to “Warning”, the group remains at status “Error”, since that is still the highest status among the items it contains.
When clicking an individual monitor item you can take a closer look at the relevant logs.
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The log both provides information about the configuration of the monitor item at execution time and also a detailed stack trace in case of errors.