[Samba] problem for joining the domain.

[Rajeev R. Veedu]

I am having a problem to join one of my machine, to the 2003 AD. I have used the same config on another machine and it works fine. I am not able to figure out where I am going wrong. I would appreciates if you could help. My samba version is 3.6.3-44 on Centos 6
 
This is what I get
 
[root at scan_srv2 tmp]# net ads join -U Administrator
Enter Administrator's password:
Using short domain name -- DOMAIN
Joined 'SCAN_SRV2' to realm 'DOMAIN.com'
DNS Update for scan_srv2.DOMAIN.com failed: ERROR_DNS_INVALID_NAME
DNS update failed!
 
My smb.config is
 
 
   workgroup = DOMAIN
   admin users = Administrator
   realm = DOMAIN.COM
   server string = Linux Samba File Server
   security = ADS
   encrypt passwords = yes
   preferred master = no
   template shell = /bin/false
   template homedir = /home/%D/%U
   idmap uid = 10000-20000
   idmap gid = 10000-20000
   enhanced browsing = no
   winbind use default domain = yes
   winbind enum users = Yes
   winbind enum groups = Yes
   winbind nested groups = Yes
   winbind separator = /
   server string = scan_srv2
   netbios name = scan_srv2
   password server = 192.168.1.223
   debuglevel = 10
[Data]
        comment = P drive and T drive
        path = /Data/Data-01/
        writable = yes
        guestok = yes
        nt acl support = yes
        #inherit acls = yes
        #inherit permissions = yes
 
My krb5.conf
 
[logging]
 default = FILE:/var/log/krb5libs.log
 kdc = FILE:/var/log/krb5kdc.log
 admin_server = FILE:/var/log/kadmind.log
 
[libdefaults]
 default_realm = DOMAIN.COM
 dns_lookup_realm = true
 dns_lookup_kdc = true
 ticket_lifetime = 24h
 renew_lifetime = 7d
 forwardable = yes
 
[realms]
 DOMAIN.COM = {
  kdc = projects01.DOMAIN.com
  admin_server = 192.168.1.223
  default_domain = DOMAIN.com
 }
 
[domain_realm]
 .kerberos.server = DOMAIN.COM
 .DOMAIN.com = DOMAIN.COM
[kdc]
profile = /var/kerberos/krb5kdc/kdc.conf
 
[appdefaults]
pam = {
   debug = false
   ticket_lifetime = 36000
   renew_lifetime = 36000
   forwardable = true
   krb4_convert = false
}