WServer Ethernet adapter fixed address gets non configured 2nd APIPA address

Question

We are facing a problem where some Windows Servers (2012, 2016) with Fixed IP addresses and DHCP running get a (non configured) 2nd IP APIPA address.

Services running on these servers for our application and the running DHCP server are having problems running on the fixed configured IPaddress.
How is it possible a Ethernet adapter gets a non configured (not configured in Ethernet IPv4 properties) APIPA IP address and how can we prevent this will happen?

Answer 1

Hi @Beekman Bas (BT-CO/MKA1.23) ,

Thanks for your feedback.

Based on provided information and discussion with my colleague, the issue may cause by gratuitous ARP. ARP may get incorrect information as the IP is already in use from some source and conflict pop will occur. This happens mostly when the server is in domain and configured with proxy servers.

Please try to disable gratuitous ARP on the windows device via regedit to see if the issue can be resolved.

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters

Set ArpRetryCount (32-bit DWORD) to 0

If there is not existed value, please create a new DWORD Value named ArpRetryCount and set the value to 0

Here is a similar thread for your reference:
Static IP devices receiving 169 address after reboot

Best Regards,
Sunny

----------

If the Answer is helpful, please click "Accept Answer" and upvote it.

Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.

Answer 2

I'd check that there aren't somehow multiple entries here.

--please don't forget to Accept as answer if the reply is helpful--

Answer 3

Hi @Beekman Bas (BT-CO/MKA1.23) ,

Thanks for posting in Q&A platform.

Based on provided info, my understanding is that we need to assign 2 IP addresses to the NIC, one should be static IP address by assigning manually and another one should be assigned IP address by DHCP automatically. Please help to correct me if my understanding is wrong.

If my understanding was correct, I'm afraid the goal cannot be achieved as I have done a test in my lab. It only can be achieved if we assign 2 static IP address to one NIC manually.

If we want to obtain IP address from DHCP server, then the DHCP server can only assign one IP to one NIC since each NIC has only one MAC address which can be identified by DHCP server.

Best Regards,
Sunny

----------

If the Answer is helpful, please click "Accept Answer" and upvote it.

Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.