Multihomed DHCP clients may cause "bad_address" entry on a DHCP Server in Windows 2000


Symptoms


A "bad_address" entry may be generated on a DHCP server. This problem may occur when the following conditions are true:

  • You have one multihomed DHCP client and one DHCP server.
  • Both network adaptors on the DHCP client and the network adaptor on the DHCP server are connected to the same segment.
  • Both network adaptors on the DHCP client are configured to automatically obtain an IP address.
  • Conflict detection is enabled on the DHCP server.
If you run the following commands on the DHCP client, one "bad_address" entry is generated on the DHCP server:

ipconfig /release
ipconfig /renew
This "bad_address" entry is the IP address that was previously assigned to the second network adaptor on the DHCP client. If you run the two commands again, another "bad_address" entry is generated on the DHCP server. In this manner, all available IP addresses in the scope become bad addresses. This could cause the DHCP server to be out of service for the scope.

Cause


Assume that nnn.nn.1.1 is assigned to the first network adaptor on the DHCP client and that nnn.nn.1.2 is assigned to the second network adaptor on the DHCP client. After you run the following command on the DHCP client, nnn.nn.1.1 is still assigned to the first network adaptor on the DHCP client:

ipconfig /release
ipconfig /renew
The DHCP server also tries to assign nnn.nn.1.2 to the second network adaptor. Because conflict detection is enabled on the DHCP server, the DHCP server tries to ping nnn.nn.1.2 before it assigns nnn.nn.1.2 to the second network adaptor on the DHCP client. Therefore, the DHCP server sends the Internet Control Message Protocol (ICMP) ECHO packet to the media access control (MAC) address of the second network adaptor on the DHCP client. The DHCP client receives the ICMP ECHO packet and passes it to the upper level. The DHCP client sends the ICMP ECHO reply packet to the DHCP server from the first network adaptor. The DHCP server then marks nnn.nn.1.2 as "bad_address".

Resolution


Service pack information

To resolve this problem, obtain the latest service pack for Microsoft Windows 2000. For additional information, click the following article number to view the article in the Microsoft Knowledge Base:
260910 How to Obtain the Latest Windows 2000 Service Pack

Hotfix information

A supported hotfix is available from Microsoft. However, this hotfix is intended to correct only the problem that is described in this article. Apply this hotfix only to systems that are experiencing this specific problem.

If the hotfix is available for download, there is a "Hotfix download available" section at the top of this Knowledge Base article. If this section does not appear, submit a request to Microsoft Customer Service and Support to obtain the hotfix.

Note If additional issues occur or if any troubleshooting is required, you might have to create a separate service request. The usual support costs will apply to additional support questions and issues that do not qualify for this specific hotfix. For a complete list of Microsoft Customer Service and Support telephone numbers or to create a separate service request, visit the following Microsoft Web site: Note The "Hotfix download available" form displays the languages for which the hotfix is available. If you do not see your language, it is because a hotfix is not available for that language.


The English version of this hotfix has the file attributes (or later file attributes) that are listed in the following table. The dates and times for these files are listed in coordinated universal time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time tool in Control Panel.

Date Time Version Size File name
--------------------------------------------------------
04-Sep-2002 06:11 5.0.2195.6044 118,896 Afd.sys
04-Sep-2002 09:07 5.0.2195.6020 105,232 Msafd.dll
04-Sep-2002 09:07 5.0.2195.6045 313,296 Tcpip.sys
30-Jul-2001 12:15 5.0.2195.3988 16,240 Tdi.sys
04-Sep-2002 09:07 5.0.2195.4874 17,680 Wshtcpip.dll

Status


Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section. This problem was first corrected in Microsoft Windows 2000 Service Pack 4.

More Information


For additional information about how to obtain a hotfix for Windows 2000 Datacenter Server, click the following article number to view the article in the Microsoft Knowledge Base:

265173 The Datacenter Program and Windows 2000 Datacenter Server product