Phantom MS Virtual Bus Network Adapter

silsuba
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Having a problem with a network adapter in a virtual server on a Windows Server 2008 Hyper-V host.   The virtual server is also running Windows Server 2008.

Some how I have ended up with a network adapter named 'Microsoft Virtual Machine Bus Network Adapter #5'.   No idea what happened to 1 thru 4!

When I try to assign a static IP to #5, I receive an error that states that the IP I am assigning to this adaptor is also assigned to an adaptor named 'Microsoft Virtual Machine Bus Network Adapter #4' and askes if I would like to remove the configuration from the absent adaptor.

I answer yes and apply the settings to #5.  Once I close out of network properties for #5, I recieve an error that Windows has detected an IP conflict.  I then do an 'ipconfig' and find that a default ip (169.254.2.XXX) is assigned to adapter #5 in place of the IP I want.

No other hosts on the network are using the IP that I am trying to assign to #5, so I have to conclude that #4 is the problem.  However, I cannot find any reference to #4 anywhere. I have checked device manager (showing hidden devices) and the registry.

I have shutdown the VM, delete and readded the network adaptor and still the problem persists.  Just to get the server back on the network, I have assigned #5 an address other than the one causing the error.  However I need this server to have the IP I was trying to config.  So, I need the server to have 192.168.1.6 and have temporarily assigned 192.168.1.20.

Another bit of behaviour that is related.  Each night at 3AM, the DNS is updated and changes the IP entry of this host from 192.168.1.20 to 192.168.1.6. So each day I must manually correct the IP in DNS in order for clients to connect.

Pleas, any advice or help will be greatly appreciated

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can you bring the server offline for a few minutes?  You could try to delete the VM.  Then add a new VM with new hardware but the old .vhd file.
Hi,

I suspect you have run into an old Windows problem

http://support.microsoft.com/kb/269155

-Saurabh
silsubaProject Manager

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Commented:
I thought we were on to something there with your link.  I was able to display all the phantom devices (0-4) and uninstall them.  Once I uninstalled, I gave the server a reboot for good measure.  Once I brought it back online, I set the IP of the remaining interface to 192.168.1.6.  No error this time, however a moment later the IP Conflict error popped up and the interface IP was changed to a 169.xx.xx.xx address.

To get the server backonline, I changed the address to 192.168.1.20.  In an effort to localize this problem to the machine in question, I looged onto another machine on the network and attempted to change it's IP to 192.168.1.6.  Same result, error stating that there was an IP Conflict and the interface was assigned a 169.XX.XX.XX address.

I then pulled up the ARP table on two different machines so I could take a look at the MAC assigned to 192.168.1.6.  It was the same in both tables.  The MAC was a Microsoft MAC, and was one digit off the MAC assigned to the interface on the Virtual Server which is having this problem.

Sobasically, no joy yet.  Any other thought or suggestions?
You got something interesting if this did not work for you
I hope there are no more pending ghost nics under hidden devices.

Here's what you can try:

First, Bounce the host see if that helps
Second, since you are unable to assign the desired ip, for now set an alternate ip. Search the registry for the IP in question and do the necessary cleanup. Ensure you 'd export the keys you are purging!
silsubaProject Manager

Author

Commented:
Can you clarify.. what do you mean by bounce the host??

Commented:
bounce the host means reboot/restart the host.

silsubaProject Manager

Author

Commented:
Thanks.  Yep.. did a complete shutdown and power up actually.  I've searched the registry for ANY ip and come up empty.  I assumed that IP information would be contained in the registry so I find it odd that I find nothing.

I'll try again..
silsubaProject Manager

Author

Commented:
Perhaps I am looking in the wrong place.  Since none of this corrected the problem I began to look elsewhere.  First.. I completly powered the virtual server off.

Then I went and took a look at the ARP tables of my switches.  Sure enough, there was an entry for 192.168.1.6 with the same MAC as I found in other places.  So I cleared this out.  Within mintes the entery was dynamically added.  So I turned to the router, and found the IP and MAC in it's ARP table as well.  So I cleared that.

Again.. added back.  So I am wondering if the Virtual Server is off.. where is this ARP map coming from.  Is it possible that the Hyper-V host has this information somewhere ??
silsubaProject Manager

Author

Commented:
Well.. I figured it out, and I was looking in the wrong place.  Someone had created a copy of the VM in question and had powered it on.  Since it was firewalled, it wasn't responding to a ping, but was adding the MAC to the ARP table of the machine pinging that particular IP.

Interesting how this all started with a phantom adapter.  Thanks for the link Signior.. that helped me remove the bogus adaptors from the machine.
silsubaProject Manager

Author

Commented:
Not the actual resolution to the problem, but this answer did help me solve the question.

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