Check_MK Werk 6021: Combined graphs: Fixed handling of optional metrics

ID: 6021 Title: Combined graphs: Fixed handling of optional metrics Component: metrics Level: 1 Class: Bug fix Version: 1.6.0i1 When trying to render combined graphs with graph templates that have optional metrics, these graphs could not be rendered. For example the "CPU utilization" graphs of some devices could not be displayed in combined graphs.