PCI/PCI-E Passthrough causing Host lock up


New Member
Aug 30, 2017
Hi guys,

I have minimal info right now and i know i should be better off writing this at home with full access to completely test as I've done before hand with the same end result.

Here it goes,

Not trying to reinvent the wheel here, most of this i am all very new to but i don't know how to read and how to google, so far no amount of searching has helped me with my issue.

I am attempt to pass through 2 NIC's to a VM in order to run Untangle, Untangle runs and appears to have no issues when using the NICS without any config, just creating a New bridge to each and dedicating it to just that.

My plan is to have 3 NIC's in Total.

NIC #1: (onboard) Used for server admin and internal network traffic
NIC #2: Used as the LAN side for the VM
NIC #3: Used for the WAN (fibre connection)

Now after a lot of testing i have been able to pass-through the iGPU for Hardware acceleration on for a CCTV VM. ( Currently de configured for testing )

I can do simple pass-through of USB hubs and port with ease.

However the killer here is that if i attempt to Pass-through 2 NICS weather one of them be the on board NIC or just both expansion NIC's the host freezes up, it wont allow power off at the power button, it requires the plug to be pulled from the rear.

I know someone is likely to hit me up about my System config, i am happy to post whatever is needed.

One of the NIC's im using is PCI-e and the other is PCI. I have used both of these in another computer with the VM OS running instead on a physical machine and it has been running for 3 months solid no issues. So that rules out hardware failure, at least for me it does.

What can i do that i have done
Note, PCI passthrough is an experimental feature in Proxmox VE.

If the passthrough makes your host unstabil, you can also create a new bridge on the host, add the physical NIC to this bridge and add only the Virtual NIC of the firewall to that bridge, so only your that firewall NIC has access to the physical NIC.

This will cost a bit of cpu time on the host, but except if you're transmitting packets at the rate of an ISP, you should not notice it.


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