We are having an issue in IPAM when the subnet scanning and the neighbor scanning overlap. When IPAM scans a subnet, all addresses that are not in use will temporarily show up in the arp tables of layer 3 devices as Incomplete, pending, etc (depending on the vendor), and in some cases (Juniper), it actually has a mac address of 000000000000 while waiting on an arp response. If IPAM then does a neighbor scan shortly after the standard subnet scan, it is finding these IP addresses in the arp table with mac address of 000000000000 and it is updating IPAM with the 000000000000 mac and marking the IP's as Used. This is causing us to have hundreds and hundreds of IP's count against our licensed limit when they are not valid.
We have already submitted a ticket regarding the update of 000000000000 mac addresses and that has already been taken care of. A patch was provided so IPAM would ignore any 000000000000 mac address found from neighbor scanning and not update the record in IPAM. However, now we are seeing the issue that IPAM still marks these IP's as used. I would like to request to disable neighbor scanning from updating IP address status. Or at the very least, if the mac address is 000000000000 or the arp request is incomplete, pending, etc, IPAM should not mark the IP as used.
