Multiple computer names using one IP Address in DNS

If you have multiple computer names using the same IP address 2003 DNS

1. Configure DHCP to do all the DNS registrations for DHCP clients and to remove DNS registrations when the lease expires.
   - Always dynamically update DNS A and PTR records
   - Discard A and PTR records when lease is deleted
2. Configure DHCP with a dedicated user account with a non-expiring password. (Advanced tab of the server property sheet.It can also to enable Windows 2000 option 002 (Release IP lease on shutdown)
3. You may have to manually clear the DNS registrations before the DHCP server can update records because the record is owned by the client instead of the DHCP server.

The problem occurs when a dynamic client, such as a laptop, that registers its own record, is disconnected from the network without releasing its IP address and therefore is not deregistering its record. Since it owns the record no other computer can update the record.

Link: http://support.microsoft.com/default.aspx/kb/816592