Hi!  I imagine this has something to do with DNS, but really can't tell what's wrong:

[root@7-3 ~]# hostname
7-3.example.com
[root@7-3 ~]# ipa-client-install -N
7-3 is not a fully-qualified hostname
The ipa-client-install command failed. See /var/log/ipaclient-install.log for more information
[root@7-3 ~]# cat /var/log/ipaclient-install.log
2019-01-04T19:27:32Z DEBUG Logging to /var/log/ipaclient-install.log
2019-01-04T19:27:32Z DEBUG ipa-client-install was invoked with arguments [] and options: {'no_dns_sshfp': False, 'force': False, 'verbose': False, 'ip_addresses': None, 'configure_firefox': False, 'realm_name': None, 'force_ntpd': False, 'on_master': False, 'no_nisdomain': False, 'ssh_trust_dns': False, 'principal': None, 'keytab': None, 'no_ntp': True, 'domain_name': None, 'request_cert': False, 'fixed_primary': False, 'no_ac': False, 'no_sudo': False, 'ca_cert_files': None, 'all_ip_addresses': False, 'kinit_attempts': None, 'ntp_servers': None, 'enable_dns_updates': False, 'no_sshd': False, 'no_sssd': False, 'no_krb5_offline_passwords': False, 'servers': None, 'no_ssh': False, 'force_join': False, 'firefox_dir': None, 'unattended': False, 'quiet': False, 'nisdomain': None, 'prompt_password': False, 'host_name': None, 'permit': False, 'automount_location': None, 'preserve_sssd': False, 'mkhomedir': False, 'log_file': None, 'uninstall': False}
2019-01-04T19:27:32Z DEBUG IPA version 4.6.4-10.el7
2019-01-04T19:27:32Z DEBUG Loading Index file from '/var/lib/ipa-client/sysrestore/sysrestore.index'
2019-01-04T19:27:32Z DEBUG Starting external process
2019-01-04T19:27:32Z DEBUG args=/usr/sbin/selinuxenabled
2019-01-04T19:27:32Z DEBUG Process finished, return code=0
2019-01-04T19:27:32Z DEBUG stdout=
2019-01-04T19:27:32Z DEBUG stderr=
2019-01-04T19:27:32Z DEBUG [IPA Discovery]
2019-01-04T19:27:32Z DEBUG Starting IPA discovery with domain=None, servers=None, hostname=7-3
2019-01-04T19:27:32Z DEBUG   File "/usr/lib/python2.7/site-packages/ipapython/admintool.py", line 178, in execute
    return_value = self.run()
  File "/usr/lib/python2.7/site-packages/ipapython/install/cli.py", line 319, in run
    return cfgr.run()
  File "/usr/lib/python2.7/site-packages/ipapython/install/core.py", line 362, in run
    self.validate()
  File "/usr/lib/python2.7/site-packages/ipapython/install/core.py", line 371, in validate
    for _nothing in self._validator():
  File "/usr/lib/python2.7/site-packages/ipapython/install/core.py", line 434, in __runner
    exc_handler(exc_info)
  File "/usr/lib/python2.7/site-packages/ipapython/install/core.py", line 458, in _handle_validate_exception
    self._handle_exception(exc_info)
  File "/usr/lib/python2.7/site-packages/ipapython/install/core.py", line 453, in _handle_exception
    six.reraise(*exc_info)
  File "/usr/lib/python2.7/site-packages/ipapython/install/core.py", line 424, in __runner
    step()
  File "/usr/lib/python2.7/site-packages/ipapython/install/core.py", line 421, in <lambda>
    step = lambda: next(self.__gen)
  File "/usr/lib/python2.7/site-packages/ipapython/install/util.py", line 81, in run_generator_with_yield_from
    six.reraise(*exc_info)
  File "/usr/lib/python2.7/site-packages/ipapython/install/util.py", line 59, in run_generator_with_yield_from
    value = gen.send(prev_value)
  File "/usr/lib/python2.7/site-packages/ipapython/install/core.py", line 636, in _configure
    next(validator)
  File "/usr/lib/python2.7/site-packages/ipapython/install/core.py", line 434, in __runner
    exc_handler(exc_info)
  File "/usr/lib/python2.7/site-packages/ipapython/install/core.py", line 458, in _handle_validate_exception
    self._handle_exception(exc_info)
  File "/usr/lib/python2.7/site-packages/ipapython/install/core.py", line 521, in _handle_exception
    self.__parent._handle_exception(exc_info)
  File "/usr/lib/python2.7/site-packages/ipapython/install/core.py", line 453, in _handle_exception
    six.reraise(*exc_info)
  File "/usr/lib/python2.7/site-packages/ipapython/install/core.py", line 518, in _handle_exception
    super(ComponentBase, self)._handle_exception(exc_info)
  File "/usr/lib/python2.7/site-packages/ipapython/install/core.py", line 453, in _handle_exception
    six.reraise(*exc_info)
  File "/usr/lib/python2.7/site-packages/ipapython/install/core.py", line 424, in __runner
    step()
  File "/usr/lib/python2.7/site-packages/ipapython/install/core.py", line 421, in <lambda>
    step = lambda: next(self.__gen)
  File "/usr/lib/python2.7/site-packages/ipapython/install/util.py", line 81, in run_generator_with_yield_from
    six.reraise(*exc_info)
  File "/usr/lib/python2.7/site-packages/ipapython/install/util.py", line 59, in run_generator_with_yield_from
    value = gen.send(prev_value)
  File "/usr/lib/python2.7/site-packages/ipapython/install/common.py", line 65, in _install
    for unused in self._installer(self.parent):
  File "/usr/lib/python2.7/site-packages/ipaclient/install/client.py", line 3630, in main
    install_check(self)
  File "/usr/lib/python2.7/site-packages/ipaclient/install/client.py", line 2106, in install_check
    rval=CLIENT_INSTALL_ERROR)

2019-01-04T19:27:32Z DEBUG The ipa-client-install command failed, exception: ScriptError: 7-3 is not a fully-qualified hostname
2019-01-04T19:27:32Z ERROR 7-3 is not a fully-qualified hostname
2019-01-04T19:27:32Z ERROR The ipa-client-install command failed. See /var/log/ipaclient-install.log for more information
[root@7-3 ~]# rpm -qv ipa-client 
ipa-client-4.6.4-10.el7.x86_64
[root@7-3 ~]# cat /etc/hosts
127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4
::1         localhost localhost.localdomain localhost6 localhost6.localdomain6
[root@7-3 ~]#