Does MAD need an IP address on the interfaces

Yes.

MAD can be only configured on Layer 2 interfaces and MAD packets are BPDU packets. Because the Management interface is a Layer 3 interface andcannot work at Layer 2, MAD cannot be configured.

Yes, but you are advised to plan consistent IP addresses for the IPMI interface of each node for the ease of remote node management. In addition, you are advised to plan all IP addresses in a management network segment that is usually a private network segment. The private network segment has no requirements on the number of IP addresses and allows requests for application.

After the Trap IP address management is set, the alarms are sent to the specified application server or maintenance terminal. The ISM provides the function of setting the Trap IP address for the alarms. Through this function, the alarms about the storage devices managed by the ISM client can be reported to another network management system (NMS) or a device with the specific IP address. If the alarm is reported in SNMP mode, the trap IP address needs to be set.