Force a different IP address using DHCP

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You may find you need to force a different IP address using DHCP in order to test something network related. Unfortunately, there is no official way to do this, and DHCP servers are designed to attempt to give the same IP address to the same machine each time it requests one if it has the ability to, so you'll have to resort to a variety of tricks.

Change Local MAC Address

If your Ethernet driver supports local MAC addresses, changing the MAC should result in a new IP. To change it in Windows, do the following:

  1. Open Device Manager.
  2. Expand Network adapters, right-click on your network connection, and select the Properties menu item.
  3. Click the Advanced tab.
  4. In the Property list, click on the Locally Administered Address item. If it doesn't exist, you cannot use this method of getting a new IP address.
  5. Select the custom Value option and enter a MAC address that is different than your current one, like 123412341234.
  6. Click OK. Your network card should automatically disconnect and request a new IP address from the DHCP server. Since your MAC address is different, the server will most likely give you a new IP address.