[Samba] Winbind File Server Domain Member Errors: "Client not found in Kerberos database" / "Could not receive trustdoms".

[Martinx - ジェームズ]

Guys,

I'm seeing the following error at my Samba4 Domain Member File Server:

---
==> /var/log/samba/log.wb-DOMAIN <==
[2014/08/16 05:39:26.616878,  0]
../source3/libads/kerberos_util.c:74(ads_kinit_password)
  kerberos_kinit_password FILE-SERVER$@REALM.DOMAIN.COM failed: Client not
found in Kerberos database
[2014/08/16 05:39:26.616962,  1]
../source3/winbindd/winbindd_ads.c:122(ads_cached_connection_connect)
  ads_connect for domain DOMAIN failed: Client not found in Kerberos
database

==> /var/log/samba/log.winbindd <==
[2014/08/16 05:39:27.256066,  1]
../source3/winbindd/winbindd_util.c:316(trustdom_list_done)
  Could not receive trustdoms
[2014/08/16 05:39:28.257587,  1]
../source3/winbindd/winbindd_util.c:316(trustdom_list_done)
  Could not receive trustdoms
[2014/08/16 05:39:29.258850,  1]
../source3/winbindd/winbindd_util.c:316(trustdom_list_done)
  Could not receive trustdoms
---

The command "kinit user" works... Kerberos seems to be fine at
"file-server".

How to fix this permanently?!

I mean, last time I saw this messages, I did a "net ads leave / join" as a
workaround but, the problem keep appearing over and over...

Apparently, it is loosing its membership... But I don't know for sure...

It is a Samba 4.1.6 on Ubuntu Trusty.

The AD DC is also a Samba 4.1.6 + Bind9, Ubuntu Trusty too. The members
based on Windows (Desktops) are working fine.

Tips?!

Tks!
Thiago