Single Forest Multiple Child Domain with duplicate Hostnames & IP


  • I have a unique weired requirement, multiple remote sites and a central site. 

    All the remote sites are using the same IP subnet and same hostnames. I can setup domains in each remote location, only domain controllers can reach the central site with unique IP and hostname. Can I have a AD setup in this way? Is it problamatic?


    Site A Client Subnet= 192.168.10.x  DC Subnet = 10.10.10.x, SITE-A.MYDOMAIN.COM

    Site B Client Subnet= 192.168.10.x  DC Subnet = 10.10.20.x, SITE-B.MYDOMAIN.COM

    Central Site Client Subnet= 192.168.10.x  DC Subnet = 10.10.30.x, MYDOMAIN.COM

    The client hostnames are same (duplicate) at all locations. Can we have a single forest AD with two child domains with the above setup?

    Friday, April 7, 2017 4:00 PM

All replies

  • The hostnames will be fine because they're not really duplicate since each host has a unique FQDN still.  You will run into problems if each domain has it's own DHCP server(s) since you they won't know about each others and you will get duplicate IP assignment.  I'd suggest 3 separate subnets or they all need access to the same DHCP/DNS server which could cause issues with DHCP options and permissions.
    Friday, April 7, 2017 4:09 PM
  • I do not have DHCP environment, all static IP assignment, Unfortunately I cannot change the IP address or change the hostnames
    Friday, April 7, 2017 4:28 PM
  • Can we have a single forest AD with two child domains with the above setup?

    As mentioned DC hostnames same but FQDN is not,so your all client's belongs to their DC and authenticate from their DC.Your DC subnet seems to be OK also.(if i understand correctly this is a root and 2 child domain.)

    Just recommend that maybe change client subnet on central site,different than 192.168.10.X.,also i would prefer to configure different client subnets on site's.Maybe first you should make sure network topology at first.

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

    Friday, April 7, 2017 6:46 PM