Weird APIPA Address

[tfxrowe]

I searched the forums to see if anyone has had this issue and it seems the only solution is to reboot the host. But before I do that I just want to see for myself.

It seems that three of my server 2008 VMs are APIPA address and when I try to disable them it says duplicate IP addresses. I tried adding different address to other VMs and they get the same thing to. These three servers in particular are never rebooted and I've looked everywhere to see if their was a conflicting IP, but their isnt.

[Virtualinfra]

Just Guess..

1. IP's in DHCP Pool, might be configured for any of the server as a static IP.

2. Try to ping the IP that is showing as IP conflict and isolate the issue.

By default APIPA is enabled if you enable DHCP.

Disabling the APIPA

1. Open Registry Editor (choose Start and then Run and then type regedit).

2. Navigate to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Servic es\Tcpip\Parameter\_Interfaces\<AdapterName> (where AdapterName is the hexadecimal representation of the network adapter in question).

3. Right-click on the <AdapterName> key and choose New and then select DWORD Value.

4. Enter IPAutoconfigurationEnabled to rename the DWORD value.

5. Double-click the new value and ensure that 0 is entered as the value data.

6. Click OK and close the Registry Editor.

So disable APIPA and try configuring it also do a ipconfig release and renew if your using DHCP or try configuring with static. Also make sure that IP is not reversed in DHCP IP pool..

[rickardnobel]

tfxrowe wrote:

It seems that three of my server 2008 VMs are APIPA address and when I try to disable them it says duplicate IP addresses. I tried adding different address to other VMs and they get the same thing to.

So three of your virtual machines with static addresses get these warnings? When you say that you tried other "different address to other VMs", do you mean that you tried configured another VM with this specific IP address and got the same warning? If so, it really points to that you have a IP conflict in the network.

[tfxrowe]

I tried with another VM and got the same issue, I finally found a technet in regards to the issue because its been driving be crazy. I've been going through my Cisco router and switch like a mad man. Seems like the proxy ARP was causing this odd conflict, which makes sense because on my Cisco switch I could see in the mac address table that the request was incomplete. So in this article all you do is reset the IP and use a registry hack for it, I've used it on two of the three VMs and it has worked. I can't use it on the third because I can't take it down just yet.

http://social.technet.microsoft.com/Forums/en-US/windowsserver2008r2networking/thread/d7bda315-6366-...