How to Install a BDC in a Routed TCP/IP Environment

When an installation of a backup domain controller (BDC) is performed, the primary domain controller (PDC) must be available to establish the computer account and the Security Identifier (SID) for the new BDC. If the protocol being used is TCP/IP and, in order to form a connection to the PDC, TCP/IP must be routed, name resolution for the domain name and the computer name must be established during the Network setup.

Name resolution for connectivity to the primary domain controller can be established by using one of the following methods:

• Enter a primary and, optionally, a secondary WINS server where the PDC has registered the domain<1Bh> entry.
  
  -or-
• Use an LMHOSTS file that has at least an entry for the PDC as follows:

  <;PDC IP address>;  "DOMAINNAME   \0x1B"  #PRE
  							

  NOTE: There must be exactly 20 characters inside the double quotes.For additional information, click the article number below to view the article in the Microsoft Knowledge Base:
  180094  (http://support.microsoft.com/kb/180094/EN-US/ ) How to Write an LMHOSTS File for Domain Validation
  180099  (http://support.microsoft.com/kb/180099/EN-US/ ) Troubleshooting LMHOSTS Name Resolution Issues

During installation, if WINS servers are not available, the LMHOSTS file can be used by importing it from a floppy disk or from an existing physical drive on the computer being installed. The location for importing the LMHOSTS file is in the Advanced options in the TCP/IP configuration dialog during Network setup. This must be completed during the portion of Setup where you configure the properties of the TCP/IP protocol.

If the PDC cannot be located during setup, you will get the following error message: If you get this message, check the following:

• Adapter configuration settings.
• Default gateway configuration on the adapter.
• If using WINS to locate the PDC, make sure the WINS server you are pointing to contains the 1Bh registration for the domain name.
• Check the syntax of the LMHOSTS file.

At this point, installation must be restarted. Going back to the network configuration by selecting the previous screen boxes will not reinitialize your TCP/IP configuration settings.

NOTE: If you are installing a Windows NT 4.0 domain controller, restarting the server will restart the installation at the GUI portion of setup. Previous versions of Windows NT require setup to be restarted from the beginning.

This scenario is not an issue for a server non-domain controller, as that type of installation is capable of becoming part of a workgroup where membership in the domain is not mandatory during setup.