Passthrough of SATA controller to Truenas VM caused Proxmox server to lose internet access.

N

NathanBradley

New Member
Apr 26, 2025
2
0
1
Please Help!!!
I have been trying to setup my hard-drives to spin down through my Truenas VM as my drives are only accessed every couple days. However I was told that I had to reconfigure to have PCIE passthrough to the SATA controller instead of just direct drive passthroughs so that Truenas has control. Stupidly instead of asking here first I just went into the VM device settings, and added a PCIE device. (In the dropdown I selected one that had SATA in the name), then I proceeded to remove the drive mappings and restart the VM.

The system became unresponsive and I realised it had lost connection to the network. I manually turned it off and on again to no avail. I then went and grabbed a monitor and keyboard. initially I was stressed because the first few USB ports I used were unresponsive however luckily I found one that wanted to work.

As of now I'm directly connected with a monitor and keyboard and I'm too scared to touch anything. How do I fix what I have done?

Thanks in advance! - Nathan

P.S. I'm new to forums so idk if this is posted in the right place. Yes I have tried searching and I haven't found anything that makes sense to me.
 
Did you check your IOMMU groups: https://pve.proxmox.com/wiki/PCI_Passthrough#Verify_IOMMU_isolation ? If not, you might want to learn about IOMMU groups on this Wiki/manual/forum and other internet resources.

You can prevent VMs with PCI(e) passthrough from starting by disabling IOMMU/VT-d/AMD-Vi temporarily in the motherboard BIOS or the kernel command-line in the Proxmox boot menu. Then you can disable the start at boot or remove the passthrough from the VM. There are several threads about this on this forum.
 
Thank you very much for your help. I just finished working through a solution on the LTT Forum.
https://linustechtips.com/topic/161...ver-to-lose-internet-access/#comment-16714033

If anyone has the same problem and the link above is expired or something... use a combination of the below

nano /etc/pve/qemu-server/<vmid>.conf
If you don't know the vmid just cd into the directory and try them all until you fine the correct one you are looking for.
Hint they normally (unless specified otherwise) start off at 100 and go up by one for each consecutive VM

look at the output of lspci to know what to get rid off

In my case I had to remove the line hostpci0: 000:16:00

Good Luck!
 
You must log in or register to reply here.
Top Bottom