13.2. DNS requirements for IdM clients
Client installer by default tries to search for _ldap._tcp.DOMAIN DNS SRV records for all domains that are parent to its hostname. For example, if a client machine has a hostname client1.idm.example.com, the installer will try to retrieve an IdM server hostname from _ldap._tcp.idm.example.com, _ldap._tcp.example.com and _ldap._tcp.com DNS SRV records, respectively. The discovered domain is then used to configure client components (for example, SSSD and Kerberos 5 configuration) on the machine.
However, the hostnames of IdM clients are not required to be part of the primary DNS domain. If the client machine hostname is not in a subdomain of an IdM server, pass the IdM domain as the --domain option of the ipa-client-install command. In that case, after the installation of the client, both SSSD and Kerberos components will have the domain set in their configuration files and will use it to autodiscover IdM servers.