HyperV and Broadcoms

On November 1, 2014, in news, by susan

Okay so it all started with a new server.  One that I want to use as a test, so I’m putting an exact copy of my real server on it in order to do this test.  But obviously it cannot be on the same IP range as the real server.  So no problem, I’ll put in a virtual router in order to do this.  So I put in a Sophos virtual router in order to facilitate this.  http://fastvue.co/sophos/blog/how-to-deploy-sophos-utm-on-hyper-v-in-7-simple-steps/ 

If you follow that blog post, the DHCP broadcast from the real DHCP server will bleed through to the virtual server set up in the test bed.  So while those blog post instructions get you most of the way, you’ll need to set up the virtual switch with the internal nic being set as “private”, not connected to a external network as shown there.

But that’s where I ended up hitting a bit of a brick wall.  No matter what I did, the connections would not get out to the Internet nor with they even do the most basic of ping commands.

In looking around the web, I found that my dear friend Broadcom nics were nailing me again and that PowerShell would come to my rescue.

For background read here:

How To Avoid Common Networking Issues In Hyper-V | Aidan Finn, IT Pro:

and here

Hyper-V 2012R2 failing network connectivity using fully converged networking SOLVED! | MS Sec by Ben:

And review this KB

Poor network performance on virtual machines on a Windows Server 2012 Hyper-V host if VMQ is enabled:

and and this KB:


I had to go into PowerShell and disable the Vmq on each nic.

Set-NetAdapterVmq -Name “NIC 1” -Enabled $False

Set-NetAdapterVmq -Name “NIC 2” -Enabled $False

Mind you I have a later network driver, but even with the most recent HP/Broadcom driver I still was having no ability to even ping from any virtual machine set up on the virtual switch.

I also set the MAC addresses to dynamic to ensure that wasn’t nailing me as well.

Set-VMNetworkAdapter –ManagementOS -Name <VirtualNetworkAdapterName> -DynamicMacAddress

Then I ripped out all the networking/virtual switches and rebuilt them and then I finally got the setup I needed.  
One virtual SBS server on a private IP range not connecting at all to the real internal lan network.
One Sophos router that is able to provide internet access to the private network.

Now we're set.
And lesson learned, even WITH the latest drivers, Broadcom network cards and HyperV lead to a lot of head banging.

One Response to HyperV and Broadcoms

  1. Allister says:

    Every Dell I sell (which default to Broadcom cards) has the Intel option added for a reason…