[Samba] Rejoining a domain as a DC

[Michał Półrolniczak]

I never had windows ad dc in my env, so I can't be 100% sure, my knowledge is based on this grouplist and my experience with samba but: 

Looking at this: https://wiki.samba.org/index.php/Demote_a_Samba_DC make me feel that I can be right about demoting, 
which is here: http://technet.microsoft.com/en-us/library/cc740017%28v=ws.10%29.aspx 

For puropse of this i would make a full parition backup on that windows server just in case. 

before that run both controllers, and try adding DNS record via Microsoft DNS Tool that is included in administration tools for ad. 
There you can switch on which controller you want to add the record. 

I remamber reading that alot of things fail if you wont demote controler, because the second one is just replication and not the master one. 

Hope this helped