The data collection failure at an interface may occur due to the following reasons:
Cause: The credentials may not have been properly associated with the device. OpManager will not be able to fetch data if improper/wrong crdentials are provided.
Solution: Use the Test Credentials option and check if the selected credentials are associated properly. If not, provide the correct credential and rediscover the device.
Cause: The selected interface may be in the Unmanaged state. Data collection will be stopped if the devices are moved to the unmanaged state.
Solution: Make sure the necessary devices and interfaces are in the Managed state. For more information on why interfaces are moved to unmanaged state, visit https://www.manageengine.com/network-monitoring/faq/why-some-interfaces-unmanaged.html
Cause: OpManager may have issues in fetching the response for OIDs that are used for data collection or the response request would have been timed out due to unresolved DNS name.
Cause: The IP Address of the device may not be reachable. In such cases, OpManager assumes the parent device to be down and terminates data collection.
Solution: OpManager generally uses the IP address of a device for status polling. But, in places where devices are implemented with dynamic IP address, you can configure OpManager to conduct status polling using the DNS name of the device. To enable this, go to Settings -> Monitoring -> Monitor Settings and change the 'Poll Using' option to DNS.
Cause: Newly discovered interfaces will not have any data to display. In OpManager, the default polling interval for an interface is 15 minutes. Which implies, no data will be available until the first polling is completed.
Solution: Specify the preferred polling interval and wait for the first set of data be collected.