Does runZero age out IP addresses?

runZero ages out offline and stale assets, but not addresses. Instead, addresses are moved around or deleted based on what replies to a scan.

If an asset is scanned but then changes IP, it will remain the same asset with the same unique ID, but be moved to a new IP address. 

If an IP address is scanned but the device found doesn't match the asset that was last seen at that IP address, a new asset will be created, and the old asset set offline (unless it still has other IP addresses that do respond to the scan).

Another way to look at it is that the set of addresses associated with an asset is determined by the addresses it responded to when it was last scanned. Addresses that were within the scope of the scan, but which sent no response, are removed from any assets they were associated with.

For example, if you scan 10.0.1.0/24, any address in that subnet that doesn't respond during the scan will be removed from the asset that address was associated with.