Primary Domain Controller (PDC) & Additional Domain Controller (ADC) concept in server 2012


  • I want to know concept about PDC and ADC details. Before the concept was PDC and BDC then PDC/ADC. Now what is the new concept regarding Active Directory 2012 server. Please clarify me. your cooperation will be highly appreciated.




    Wednesday, January 11, 2017 7:25 AM

All replies

  • Hi

     For server 2012 r2 it's called replica & additional domain controller.And recommendation is only configure PDC&ADC with ADDS,DNS(ad integrated),GC roles.(do not configure any other roles on dc's.).ALso at least there should be min one ADC is recommended.

    Also you can check this ms article about your question;

    This posting is provided AS IS with no warranties or guarantees,and confers no rights. Best regards Burak Uğur

    Wednesday, January 11, 2017 8:09 AM
  • You can take it that way: DCs could be RW or RO, they can have a global catalog and hold FSMO roles. The best practices for FSMO roles and how you can assign them as advised here:

    This posting is provided AS IS with no warranties or guarantees , and confers no rights.

    Ahmed MALEK

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    Thursday, January 12, 2017 11:05 PM
  • Hi,

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    Monday, January 16, 2017 8:58 AM
  • I am not clear with provided description. Any web link for clearing the concept.


    Friday, January 20, 2017 11:47 AM
  • The terms PDC and BDC only applied to Windows NT domains. Since Windows 2000 server, the terms have been just Domain Controller (DC) and member servers. Each DC can host one or more FSMO roles, one of which is the PDC Emulator role. Plus, any DC can also host the GC role. The PDC Emulator role has several functions, one of which is to act as a PDC if the network has any Windows NT clients. That function is just about never necessary now, but there are many other critical functions (time source, password changes, account lockout, etc.)

    The only time I have ever seen reference to ADC (additional Domain Controller) has been in forum questions. A search on such an acronym is not easy, but I found only references to AD DC and Analog-Digital Converter. I don't believe Microsoft uses this acronym at all. Yes there is only one DC in the domain with the PDC Emulator role, but I see no reason to refer to all other DC's as ADC's.

    Edit: Relevant links:

    and specifically on the PDC Emulator role:

    Edit: This is what I found when I searched on "Additional Domain Controller":

    The article title is "Installing an Additional Domain Controller". The acronym ADC is never used.

    As an aside, I have 3 Wiki articles documenting acronyms, one for all Microsoft technologies, one for Active Directory, and one for terms only used by Microsoft. I have collected over 700 acronyms in these articles over the years. ADC is not one of them.

    Richard Mueller - MVP Enterprise Mobility (Identity and Access)

    Friday, January 20, 2017 1:27 PM