Thanx for posting to our site.
You must keep your PF and VF drivers aligned, which you have. For the benefit of others, at this time the current driver versions are:
PF – ixgbe driver – version 3.17.3
VF – ixgbevf driver – version 2.10.3
We used to have the PF driver assign a random MAC address to the VF at creation time. Rational was that an application planning to use the VF will assign a valid MAC address. For example – Libvirt will assign a valid MAC address when VF was assigned to the VM using Virt-Manager. This worked well for a while, however as people started to use SR-IOV frequently random MAC address assignment caused udev device naming convention to malfunction during kernel boot time. Starting in ixgbe version 3.14.5 driver assigns MAC address 00:00:00:00:00:00 to VF during VF creation time. This change requires VF driver version 2.8.7 or newer for proper functionality.
Regarding MTU - the MTU of the VF must be less than or equal to the PF when using the Intel X520. This limitation was addressed in the Intel X540 device.