[Samba] Samba4 - joining linux clients to Samba subdomain

[Prema]

Dear all ,

We have installed and  setup Samba4 as Primary domain controller(pdc) in
Debian based Linux OS. I am able to join a debian machine as a client using
likewise-gui (PBIS) in the PDC.
Realm: cdacsamba.lan
Domain: cdacsamba
Similarly I have another setup of Samba4 (Secondary domain controller -
sdc1) currently running independently with debian machines as clients.
Realm: sub1.cdacsamba.lan
domain: sub1

Now i am trying to join the sdc1 as a subdomain of pdc. The requirement is
, the policies what ever i put in pdc should get synced with sdc, but the
local policies i put in sdc should not be sent back to pdc.

I tried to do the above setup using "samba-tool domain join" as DC , but
after joining I cant join and authenticate any clients to my sdc.
I also tried joining another machine to join pdc without provisioning   but
that also in vain.

Kindly guide me how to proceed and how i can join or create subdomains in
samba4 and the method of authenticating clients in a subdomain.

Thanks in advance.
-- 
Regards.,
Prema S