A new "nscfg adldap" subcommand was added in #OracleSolaris 11.4.63 to simplify the process of setting up a Solaris system to use an Active Directory server as the source of user information via LDAP.
The included OpenLDAP software was also upgraded from the 2.4 train to the 2.6 train in this release, which may require extra work if you're using it as an LDAP server. See Note 48 in the SRU 63 README and https://github.com/oracle/solaris-userland/blob/master/components/openldap/Solaris/openldap-transition.txt for more information.