After this weekends network card passthrough fail with the EXPI9404PT on VMware 6.0 I was feeling pretty discouraged, so I took a break for a day. I decided to try again today since I have a couple other models of network cards in my currently running lab:

This was actually pretty inconvenient, as I had to shut down all my VMs, shut down the host, pull the card, add the EXPI9404PT, boot up, and reconfigure all of my vSwitches with the new vmnics. It worked, but it was a step I was certainly hoping to avoid. On the plus side, newer network cards should hopefully be a little more efficient — I read something like 2.5W vs 5.6W. Not earth shattering, but it’s something!

I figured I’d save myself the hassle and start with the higher model card — just seems like I should have better luck, right?

I don’t trust it, so I check the VMware Compatibility Guide first this time. YES – Intel Gigabit ET Quad Port Server Adapter — Supported ESXi 6.0 U1 on igb version 5.2.5. Perfect.

I install it, boot it up, it’s there!

I configure the device for passthrough. It’s smart enough that I can pick individual ports — that’s cool.

Reboot to apply changes.

Comes back up — Message: “This device needs host reboot to start running in passthrough mode.”

Like an idiot, I reboot again.

Same message.


Screw it, I’m trying the older 82575GB card. Long story short: same result.

I do some researching and find out  the 82575GB was deprecated in ESXi 5.5, but “may” continue to work. I also found a site showing the same problem. It ends up Access Control Services were introduced with the direct assignment of devices. Passthrough of a PCIe device to a virtual machine, using Direct Path I/O is disallowed by the VMKernel if the device is connected to a switch that does not support Access Control Services (vmware KB 1036811).

Luckily this is my homelab, I can disable this:

Select the host and navigate to Configuration > Advanced Settings (Software) > VMkernal > Boot. Search for a parameterVMkernel.Boot.disableACSCheck and enable the check-box.

vmware disableACSCheck



Of course, now I’m using the older 82575GB card that’s deprecated.

One last network card swap, reboot, make passthrough change, reboot and finally we have a victory.

I’m not sure it was worth the $80 I saved versus just buying a new network card.


3 Responses to “X10SDV-F: VMware 6.0 Intel NIC Passthrough Fail (Part 2)”

  1. Mark S on August 30th, 2016 9:35 pm

    DUDE – holy cow I can’t thank you enough. I just gave up on my FREENAS project when I couldn’t get my 82571EB to passthrough. My LSI HBA was a no brainer but I couldn’t for the life of me get the NIC to pass through. I let it sit in my basement for the last 8 months just languishing with 12 TB of storage waiting for a purpose. THANK YOU for posting this.

  2. mike on November 17th, 2016 11:47 pm

    Absolutely. I’m happy to hear that all that misery resulted in some good for someone else.

  3. Andrew on March 23rd, 2017 6:20 pm

    Fantastic! I was thinking I may need to buy 2x 2 port cards. Have you had any issues running with this ASC check disabled?

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