$ yum install ntp
$ chkconfig ntpd on
$ ntpdate 0.pool.ntp.org
$ service ntpd start

[global]
        workgroup = EXAMPLE
        realm = EXAMPLE.COM
        server string = Samba Server
        security = ADS
        log level = 3
        log file = /var/log/samba/smbd.log
        max log size = 50
        socket options = TCP_NODELAY SO_RCVBUF=8192 SO_SNDBUF=8192
        preferred master = No
        local master = No
        dns proxy = No
        disable netbios = Yes
        name resolve order = hosts bcast
        idmap uid = 16777216-33554431
        idmap gid = 16777216-33554431
        cups options = raw
        template shell = /bin/bash
        use kerberos keytab = yes
        winbind use default domain = yes

        ldap admin dn = cn=Manager,dc=example,dc=com
        ldap idmap suffix = ou=Idmap
        ldap suffix = dc=example,dc=com
        idmap backend = ldap:ldap://ldap1.example.com

[homes]
        comment = Home Directories
        valid users = %D\%U
        read only = No
        browseable = No

[printers]
        comment = All Printers
        path = /var/spool/samba
        printable = Yes
        browseable = No

[distros]
        comment = Software Distributions
        path = /home/distros/
        read only = No
        create mask = 0777
        guest ok = Yes

[logging]
 default = FILE:/var/log/krb5libs.log
 kdc = FILE:/var/log/krb5kdc.log
 admin_server = FILE:/var/log/kadmind.log

[libdefaults]
 default_realm = EXAMPLE.COM
 dns_lookup_realm = false
 dns_lookup_kdc = false

[realms]
 EXAMPLE.COM = {
  kdc = kdc.example.com:88
  default_domain = example.com
 }

[domain_realm]
 .example.com = EXAMPLE.COM
 example.com = EXAMPLE.COM

[kdc]
 profile = /var/kerberos/krb5kdc/kdc.conf

[appdefaults]
 pam = {
   debug = false
   ticket_lifetime = 36000
   renew_lifetime = 36000
   forwardable = true
   krb4_convert = false
 }