I assume you are referring to trust relationships here?? This is the only server on this domain which is not, nor has it ever been, attached to any other domain.

If you have people logging on using NT security, even without trusts between domain you will have to shuffle the domain stuff if you are replacing the server. It involves creating the new server as a BDC, promoting it to a PDC, making sure it is all synced and then removing the old server. Or something like that...

Read the MS docs, three times !