How to have connectivity between VM on KVM using hostdev forwarding mode

Question

I'm setting up a server with an Agilio Netronome SmartNIC , which support the SR-IOV technology (to virtualize the PCIe connector, so the VM have a direct access to the materiel). My OS (Ubuntu 18.04) and my BIOS also support that technology. How can I do for having connectivity between the VM and the host ?

I have configured a network with virsh using the hostdev forwarding mode ( https://wiki.libvirt.org/page/Networking#PCI_Passthrough_of_host_network_devices ).

<network>
   <name>passthrough</name>
   <forward mode='hostdev' managed='yes'>
      <pf dev='enp2s0np0'/>
   </forward>
</network>

And I have make interfaces that I have add to my VM with the virsh attach-device command :

 <interface type='hostdev' managed='yes'>
     <source network='passthrough'>
        <address type='pci' domain='0' bus='2' slot='8' function='1'/>
     </source>
     <mac address='52:54:00:6d:90:01'/>
   </interface>

There is no problem to start the VM, the interfaces are present, with the appropriate driver, etc. but when I put IP addresses (on a same subnet, respectively 10.0.0.1/24 for the first VM and 10.0.0.2/24 and for the second) I can't ping my VM.

Does anyone know how to set the connectivity when using the SR-IOV ?

Thanks in advance :)

Answer 1

当您将设备传递到VM时，它无法工作，裸机不再与其连接，只有当NIC具有多个端口并且能够通过一个端口，以便一个仍留在裸机中并且两个端口都已连接时，才有可能到同一子网，为什么不通过虚拟功能？