The DNS name service does not support aliases for individuals. This name service does support aliases for hosts or domains that use Mail Exchanger (MX) records and CNAME records. You can specify host names, domain names, or both names in the DNS database. For more information about sendmail and DNS, see Interactions of sendmail With Name Services in Chapter 3, Mail Services (Reference), or see the Working With Oracle Solaris 11.2 Directory and Naming Services: DNS and NIS .
For more information, see Using Your Assigned Administrative Rights in Securing Users and Processes in Oracle Solaris 11.2 .
Use nslookup to ensure that an entry exists for mailhost and mailhost.domain in the DNS database. For more information, refer to the nslookup (1M) man page.