Checkmk Werk 14542: Interface checks: Stop producing constantly zero and potentially wrong metrics

ID: 14542 Title: Interface checks: Stop producing constantly zero and potentially wrong metrics Component: Checks & agents Level: 1 Class: Bug fix Version: 2.2.0i1 The interface checks process a lot of different metrics (input and output bandwidth, input and output error rates, input and and output packet rates, etc.). Before this werk, for any metric not reported by a device, the interface checks returned constantly zero values. For example, for EC2 instances in AWS, the only metrics reported by the AWS special agent are input and output bandwidth. Before this werk, the interface check constantly reported zero for all packet rates in this case. This is however useless and potentially wrong in many places. Therefore, as of this werk, the interface checks only return metrics for which the corresponding device actually reports values.