SL7.1 (EL7.1) область обнаруживать не обнаруживать

Пробуем присоединить SciLinux 7.1 (EL7.1) к домену AD, работающему на Windows 2008R2 64bit.

Следуя руководству по интеграции с Windows Red Hat Enterprise Linux 7:

$ sudo realm discover -v mems.local
 * Resolving: _ldap._tcp.mems.local
 * Resolving: mems.local
 ! Discovery timed out after 15 seconds
mems.local
  type: kerberos
  realm-name: MEMS.LOCAL
  domain-name: mems.local
  configured: no

Тем не мение:

$ nslookup -type=srv _ldap._tcp.mems.local
 Server:        172.17.21.20
 Address:   172.17.21.20#53

_ldap._tcp.mems.local   service = 0 100 389 mwinds2.mems.local.
_ldap._tcp.mems.local   service = 0 100 389 mwinds1.mems.local.

Что мне теперь делать?

# realm join mems.local
See: journalctl REALMD_OPERATION=r1063.5453
realm: Cannot join this realm

# journalctl REALMD_OPERATION=r1063.5453
-- Logs begin at Wed 2015-07-29 14:50:27 AKDT, end at Wed 2015-07-29 15:08:25 AKDT. --
Jul 29 15:08:10 playbox.mems.local realmd[5456]:  * Resolving: _ldap._tcp.mems.local
Jul 29 15:08:20 playbox.mems.local realmd[5456]:  * Resolving: mems.local
Jul 29 15:08:25 playbox.mems.local realmd[5456]:  * No results: mems.local

# nslookup _ldap._tcp.mems.local
Server:         172.17.21.20
Address:        172.17.21.20#53

*** Can't find _ldap._tcp.mems.local: No answer

# nslookup -type=srv _ldap._tcp.mems.local
Server:         172.17.21.20
Address:        172.17.21.20#53

_ldap._tcp.mems.local   service = 0 100 389 mwinds2.mems.local.
_ldap._tcp.mems.local   service = 0 100 389 mwinds1.mems.local.

$ tcping mwinds1 389
mwinds1 port 389 open.