Purging the autodiscovery list
To optimise the maintenance of the Autodiscovery list and avoid having old or out of date entries in there, the contents of list are purged according to the following rules:
All entries which have a status set to Invalid are removed from the list when the list is being refreshed according to the rules previously described (Start-up, ScanCount).
Time To Live
Each entry which has a status of Unverified status is removed from the list if its age reaches the value configured in the MaxDeviceAge parameter. This is also done when the list contents are being refreshed.
Device IP Address Change
If the IP address of the device on which the agent is running changes, the Autodiscovery module purges ALL entries in its list and immediately starts to refresh the contents. The reason for this is that typically an address change implies connection to a new network and so the existing contents of the device list are almost certainly unusable.