Hello D.G. Pratama,
NPM 10.4 added enhanced de-duplication logic into "Add node" and "Discovery" wizards. Every time you run one these wizards list of de-duplicators perform checks for possible duplicate with already monitoring nodes. Final verdict if node is duplicate or not is calculated from partial results defined by match of IP Address, DNS entry, list of MAC addresses, and SysName.
De-duplicator checks are Engine specific.
Tom P.