Configure Hyper-V NIC in Promiscuous Mode

To allow Tenable Network Monitor to monitor external traffic on a Hyper-V host, configure the virtual switch for port mirroring and set the Tenable Network Monitor VM network adapter as the mirroring destination.

1. Open PowerShell on your Hyper-V host as an Administrator.

2. Add the port monitor mode feature to the virtual switch that the Tenable Network Monitor VM is connected to. Replace <vSwitchName> with the name or ID of the virtual switch.

   $A = Get-VMSystemSwitchExtensionPortFeature -FeatureName "Ethernet Switch Port Security Settings"

   $A.SettingData.MonitorMode = 2

   Add-VMSwitchExtensionPortFeature -ExternalPort -SwitchName <vSwitchName> -VMSwitchExtensionFeature $A

3. Verify that the feature was added:

   Get-VMSwitchExtensionPortFeature -ExternalPort -SwitchName <vSwitchName> –FeatureName "Ethernet Switch Port Security Settings"

4. Change the PortMirroring attribute of the VM network adapter. You can also do this in the Hyper-V Manager GUI. Replace <VMName> with the name of the Tenable Network Monitor VM and <MACAddr> with the MAC address of its network adapter.

   Get-VMNetworkAdapter -VMName <VMName> | ? MacAddress -eq '<MACAddr>' | Set-VMNetworkAdapter -PortMirroring Destination