[Samba] DC on CentOS6.5, RDP to win7/8 issue

[Valery Efimov]

Hi,
We have installed samba4 on 64-bit CentOS6.5 and joined all our office
Win7/8 Pro desktops to that domain. We also have several Linux machines
(CentOS) in the office. All of them authenticate to the samba just fine.

Version of samba we have:
# /usr/local/samba/sbin/samba -V
Version 4.2.0pre1-GIT-60db710

However, when I try to do Remote Desktop from one Windows machine to
another, it works fine just first time, and after first successful
connection it does not allow me to login using RDP to that machine.

We suspected that it has something to do with Kerberos ticket renewal and
added these lines to the /usr/local/samba/etc/smb.conf file:

[global]
 ...
        kdc:service ticket lifetime = 24
        kdc:user ticket lifetime = 24
        kdc:renewal lifetime = 120

And in /etc/krb5.conf we have:

[libdefaults]
...
 ticket_lifetime = 24h
 renew_lifetime = 7d

But it didn't help. Basically, the way it works:
1. I reboot Windows desktop
2. I connect using RDP from one desktop to freshly rebooted - success!
3. I disconnect from the remote session using logoff, or by just closing
the windows (doesn't matter how)
4. I try connecting using RDP from any desktop to the one I am testing -
I'm getting to the login screen, then to Welcome screen that shows that I'm
being logged in, but the login never happens.

I googled the subject but could not find any solution so far.

Thanks,
Val