How to Move a DHCP Database to Another Windows NT Server

• Microsoft Windows NT Workstation versions 3.5, 3.51, and 4.0
• Microsoft Windows NT Server versions 3.5, 3.51, and 4.0

SUMMARY

Windows NT provides an administration utility called Dynamic Host Configuration Protocol (DHCP) Manager (Dhcpadmn.exe) that allows you to manage DHCP servers. However, Dhcpadmn.exe does not allow you to move a database from a server to another server. This article explains how to move a database from a server to another server if the database and backup directories are on default drive.

MORE INFORMATION

To move a database from a server computer to another server computer, perform the following procedures:

From the Source Server

1. Stop the DHCP Server service using the Control Panel Service tool.

2. To prevent DHCP from starting after the database has been transferred, disable DHCP. To do so, use the Control Panel Services tool. Select Microsoft DHCP Server from the Services list, click Startup, click Disabled, and then click OK.

3. Copy the DHCP directory tree (%SystemRoot%\system32\Dhcp) to a temporary location on the new (destination) DHCP server. For example, copy the directory tree to C:\Temp\System32\Dhcp.

For information about how to edit the registry, view the "Changing Keys And Values" Help topic in Registry Editor (Regedit.exe) or the "Add and Delete Information in the Registry" and "Edit Registry Data" Help topics in Regedt32.exe. Note that you should back up the registry before you edit it.

1. Start Registry Editor (Regedt32.exe) and go to the following subkey:

         HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\DHCPServer
         \Configuration
   

         NOTE: The above registry key is one path; it has been wrapped for
         readability.
   

2. From the Registry menu, click Save Key. Create a name for this key. For example <Temp1>.

1. Remove the DHCP directory (%SystemRoot%\System32\Dhcp).

2. Click the Start button, point to Settings, click Control Panel, and then double-click the Network icon.

3. Click the Protocols tab, select DHCP from the Network Protocols list,

       and then click Remove.
   

From the New DHCP Server

1. If you have not already installed the DHCP Server software, install it and then restart the server.

2. Stop the DHCP Server service.

3. Rename the System.mdb file in the temporary System32\Dhcp directory to System.src.

   NOTE: In Windows NT 3.5, copying the System.mdb file from one system to another can cause problems.

4. Copy the DHCP directory tree from the temporary directory to %SystemRoot%\system32 to replace the existing DHCP directory.

5. Start Registry Editor (Regedt32.exe) and go to the following subkey:

         HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\DHCPServer
   

6. Select Configuration under the DHCPServer subkey.

7. From the Registry menu, click Restore.

8. Select %SystemRoot%\System32\Dhcp\Backup\Dhcpcfg.

9. When prompted, click Yes.

   NOTE: After clicking Yes to the prompt to overwrite the existing registry entries, you may get the following error message:

         Registry editor could not accomplish the requested operation.
   

   This error can be caused by trying to remotely restore the registry from one system to another, as indicated in the following Microsoft Knowledge Base article:

         ARTICLE-ID: Q139600
         TITLE     : Registry Editor Save Key Saves Key on Wrong Computer
   
      But, this error can also be caused by clicking Save Subtree As rather
      than the Save Key option as indicated in step 5 above when carried out
      on the previous (source) server.
   
   

10. Exit Registry Editor.

11. Start the DHCP service.

12. Start the DHCP Manager.