Kerberos が Active Directory に参加できませんでした。

Ubuntu 12.04.05でActive DirectoryとSamba 4に参加しようとしました。
実行するとhost -t SRV _kerberos._udp.test.sgエラーが発生します。

Host _kerberos._udp.test.sg not found: 3(NXDOMAIN)

同時に

$# host -t SRV _ldap._tcp.test.sg 
_ldap._tcp.test.sg has SRV record 0 0 389 4ecapsvsg6.test.sg.
$# host -t A 4ECAPSVSG6.test.sg
4ECAPSVSG6.test.sg has address 10.153.64.5

私のもの/etc/samba/smb.conf：

# Global parameters
[global]
   workgroup = TEST
   realm = TEST.SG
   netbios name = 4ECAPSVSG6
   server role = active directory domain controller
   dns forwarder = 10.153.64.5
   security = ads
   use kerberos keytab = true
   password server = 4ecapsvsg6.test.sg
   allow dns updates = nonsecure and secure
   bind interfaces only = no
   server services = +smb -s3fs
   dcerpc endpoint servers = +winreg +srvsvc
   passdb backend = samba4
   server services = smb, rpc, nbt, wrepl, ldap, cldap, kdc, drepl, winbind, ntp_signd, kcc, dnsupdate, dns 

私のもの/etc/krb5.conf：

[libdefaults]
    default_realm = TEST.SG
    krb4_config = /etc/krb.conf
    krb4_realms = /etc/krb.realms
    kdc_timesync = 1
    ccache_type = 4
    forwardable = true
    proxiable = true
[realms]
     4ECAP.SG = {
          kdc = 4ecapsvsg6.test.sg:88
          admin_server = 4ecapsvsg6.test.sg:749
          default_domain = test.sg
    }
[domain_realm]
    .test.sg = TEST.SG
    test.sg = TEST.SG
[login]
    krb4_convert = true
    krb4_get_tickets = false

私のもの/etc/hosts：

  127.0.0.1       localhost
  127.0.1.1       4ecapsvsg6
  # The following lines are desirable for IPv6 capable hosts
  ::1     ip6-localhost ip6-loopback
  fe00::0 ip6-localnet
  ff00::0 ip6-mcastprefix
  ff02::1 ip6-allnodes
  ff02::2 ip6-allrouters
  10.153.64.5     4ecapsvsg6.test.sg     4ecapsvsg6

解決策は何ですか？これがないと、次のコマンドを使用してドメインに参加できません。

sudo net ads join

このようなエラーが発生します

Failed to join domain: failed to lookup DC info for domain 'TEST' over rpc: Logon failure

私はそれをし、結果は次のとおりですkinit administrator。klist

   Ticket cache: FILE:/tmp/krb5cc_0
   Default principal: [email protected]
    Valid starting       Expires              Service principal
    26/03/2015 14:29:04  27/03/2015 00:29:04  krbtgt/[email protected]
    renew until 27/03/2015 14:29:00