Hi all,

I'm trying to create external virtual switch on newly installed HyperV 2012 R2 server.

I'm using the same NIC with host server, and Allow management OS to share this network adapter is checked. When I click Apply i get following error after 5-10 min of delay:

Adding ports to the switch 'LAN' failed.

The operation failed with error code '-4'.

After that server becomes unavailable for network communication.

Any help on this issue will be appreciated.

Hi 

Just check in Network and sharing center and if there is a Virtual Switch created delete it. Set static IP to the default network connection and then try again. 

Also are you able to create Internal or Private network Switch.

Hello Sergey,

Can you make sure that the latest drivers are installed for the manufacturer card?

Please try to clear all settings under Properties (Control Panel\Network and Internet\Network Connections) for that particular NIC and then try to re-create the External Virtual Switch.

I hope this answer will help.

Re

Hello, thanks for answers.

I tried to recreate Switch and got the same problem. Also I tried to use another NIC and I was able to create Virtual Switch, but after reboot server became unavailable.

I'll try to create internal/public switches and share results.

Hello Sergey,

Thanks for the update.

What kind of Server hardware are you using?

Is it updated with the latest Hardware firmware and drivers?

I feel something around this corner.

Re

Actually, this is not a server machine, this is workstation with HyperV 2012 R2 installed.

NIC is Intel pro 100, and I see that drivers must be included into OS

http://www.intel.com/support/network/sb/CS-006103.htm?wapkw=pro+100+driver

Second NIC is Realtek integrated with mainboard. I'll try to setup latest drivers and firmwares and let you know.

• Marked as answer by Elton_JiMicrosoft contingent staff, Moderator Tuesday, March 25, 2014 1:37 AM

Hi Sergey,

How are things going ?

Best Regards

Elton Ji

Hello,

Sorry for delay, I was at business trip. I decided to install HyperV 2012 without R2 and everything went fine. So, I think that the problem was related to drivers. If I need to upgrade OS to R2 later I'll try to setup another NIC.

• Edited by Sergey Stepanov Friday, March 28, 2014 5:54 AM

I also experience the same issue when the first time I tried to add the virtual switch.

I tried to uncheck the "allow management OS to share the NIC" and press ok to add the switch, still the same error.but when I tried 2nd time, I was successful. and after this, I edit the property by check the "allow management os to share", it worked.

I remove completely the switch and add it back by having 'allow mgmt. os to share" checked, this time, the error does not come up...

not sure what exactly happens internally, but you could try the similar steps.