First thing first

Step 1: Check that the Intel Ethernet Server Adapter. For more information, do take a look at Using SR-IOV with Intel® Ethernet Server Adapters

In a nutshell, You blacklist the vf driver in the host, and enable the VFs as part of the kvm guests.

Step 1: Add a line /etc/modprobe.conf

options ixgbe max_vfs=8

The above configuration will create 8 Virtual Nics per Port. The Intel Card supports up to 64 FVs.

Step 2: Blacklist the ixgbevf driver by creating a file called /etc/modprobe.d/blacklist-ixgbevf.conf

blacklist ixgbevf

Step 3: Reboot the machine