Abstract: Technologies are provided for identifying problems with network monitoring agents. For example, a network monitoring agent that is experiencing network packet loss can be examined to determine if it is degraded. For example, metrics can be obtained that are associated with the network monitoring agent. The obtained metrics can then be evaluated against thresholds. For example, if a high confidence metric is outside of a threshold for the high confidence metric, then a determination can be made that the network monitoring agent is degraded. As another example, if two low confidence metrics are outside of respective thresholds, then a determination can be made that the network monitoring agent is degraded. If a network monitoring agent is degraded, then its monitoring data can be discarded.

Abstract: In one embodiment, detection of failures in a network device can be achieved by obtaining a last hop of partial traceroutes. For example, the last hops of the partial traceroutes detected in a time period can be sorted by frequency of occurrence. Multiple clusters can be generated, one with last hops that are most frequent and at least one other with the last hops that are less frequent. The hop with the highest frequency and the last hop with the second highest frequency can be compared. If the last hop with the highest frequency exceeds the second highest frequency by a predetermined amount, then the last hop with the highest frequency is alarmable.