In the practical projects, for example, a server device is the domain controller and FTP and E-mail, but not with the DNS server, another server equipment is designed as a DNS server, don't add other role services,
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So the question comes, without the presence of a domain controller that the DNS server will not be able to create the SRV records, no SRV record user client cannot join the domain, if add on special DNS server domain controller will not exist to create the SRV records, also can put the server device configured to additional domains, but actually only need two separate servers that how to set?