DHCP Reservations Show an Expiration Date

ID: Q189009

The information in this article applies to:

Microsoft Windows NT Server version 4.0

SYMPTOMS

When a DHCP database becomes corrupted, it may be necessary to rebuild the database from the registry.

For additional information, please see the following article in the Microsoft Knowledge Base:

ARTICLE-ID: Q173396
TITLE : How to Restore a Corrupted DHCP Database File

After doing the reconcile, when you view the properties for a client lease, the computer name will be listed as the IP address of the lease and an arbitrary hexadecimal value will be listed as the client identifier. These will be replaced with the appropriate information as the clients renew their leases.

You will also notice that reservations now have a lease expiration. Normally, reservations should have "Infinite" for Lease Expires: under Client Properties (or N/A if the client has never actually leased the reserved IP address).

The lease expiration date will also be reseated back to Infinite when the client renews its IP address.

There is one scenario when this does not happen.

If you go to Active Leases, double-click the reservation and select OK to exit, the following message will be displayed:

The Unique Identifier you have entered may not be correct. Do you want to use this Identifier anyway?

If you select Yes, the client will NOT get its reserved IP address. Instead it will get the next available IP address from the scope.

RESOLUTION

This problem can be fixed by going back to the reservation before the client renews and replacing the arbitrary hexadecimal value listed as the client Unique Identifier with the media access control address for the client.

If you try to change the hexadecimal value after the client has already renewed and received a different IP address, you will get the following error:

An error occurred while accessing the DHCP database; look at the DHCP server event log for more information

You will also receive the following message in Event Viewer:


   Event ID   : 1014
   Source     : JET
   Description: The JET Database call returned the following Error: -1605.

This happens because the client media access control address is already in the database.

At this point, you can release the IP address from the client side (Ipconfig.exe /RELEASE on Windows NT or Winipcfg.exe and select Release on Windows 95), and enter the media access control address to the reservation again. The client will be able to lease its reservation now.

STATUS

Microsoft has confirmed this to be a problem in Windows NT Version 4.0. We are researching this problem and will post additional information here in the Microsoft Knowledge Base as it becomes available.

Keywords : kbbug4.00
Version : WinNT:4.0
Platform : winnt
Issue type : kbbug