myhostname = mail.example.com

virtual_alias_domains = ldap:/etc/postfix/ldap/virtual_alias_domains
virtual_mailbox_domains = $myhostname

virtual_alias_maps = ldap:/etc/postfix/ldap/virtual_alias_maps
virtual_mailbox_base = /
virtual_mailbox_maps = ldap:/etc/postfix/ldap/virtual_mailbox_maps
virtual_uid_maps = ldap:/etc/postfix/ldap/virtual_uid_maps
virtual_gid_maps = ldap:/etc/postfix/ldap/virtual_uid_maps

smtpd_sender_login_maps = ldap:/etc/postfix/ldap/smtpd_sender_login_maps