IP address conflict?

Question

Computer networks

Good afternoon, it may seem like a fantasy, but the situation is this.
There is a network of the enterprise all computers with static ip addresses, there is an HP server on which two network cards one of which is switched off programmatically and the cable is not connected to it. At one point, one of the computers gave an error about the ip address conflict, and the address on it had to be changed. Ping to this ip address does not go, but if you run it through the arp-ping.exe utility, it passes and gives out the mac of the "pest".
After it turned out which mac address the conflict comes from, the search led to the HP server, and here is the most interesting thing, after looking through all the mac addresses on the network, the mac of the "pest" did not look like any of those on the network, except for the mac address of the server, but the last sign was different. Those. if the mac of the first network is 00:00:00:00:00:00:00, the second is 00:00:00:00:00:00:01, and the "wrecker" is 00:00:00:00:00:00:03 . If I turn off the network programmatically in Windows, then nothing changes, and if I pull out the cable, then the ping through arp-ping disappears, the cable appears. Only one network is configured on the server, there is 1 of its ip, which was assigned to it from the very beginning, a mask, a gateway and 1 dns. The same situation appeared with another same server, only the ip that it took was different. And where should I dig? Or did I go the wrong way in the first place?

Answer 1

Maybe an IPMI/iLO interface?

And so I thought the same thing.