Category Archives: Hyper-V

Configuring Jumbo Frames on a Hyper-V/Server Core Virtual NIC

I was recently reading two excellent articles on NIC configuration for server core and virtual NICs.  The reason I happened upon these postings was because I was searching for a way to enable Jumbo Frames.  Unfortunately, I didn’t find anything that specifically addressed doing this work on vitrualized NICs in Hyper-V Server, which is slightly different than physical NICs. 

Using Michael Platt’s article, I discovered that it did not take into account multiple NICs with the same device name.  What I really needed was a way to reference the “Friendly Name” (the one you set in the Hyper-V Virtual Network Manager).  After doing a search of the registry, I found that the friendly names of the virtual NICs are stored in 

HKLM\SYSTEM\CurrentControlSet\Enum\Root\VMS_MP\

From there, one can search for the correct NIC as described in the article, using the “Driver” value.

As an aside, you can lookup the GUID for physical drivers by running a search of the friendly name in

HKLM\SYSTEM\CurrentControlSet\Control\Network\

The containing key will match the NetCfgInstanceId of the NIC you want to modify. 

Using these methods, you can be sure you’re configuring the correct NIC within the registry.