Hello everyone, I am currently installing a virtual machine on Unraid. The system I installed was debian12, and in order to connect a 4-port 2.5G network card directly, I selected one port to the virtual machine (VM1). However, when VM1 started and the installation went through network detection, the host restarted abnormally. I have tried security drivers and even tried using a Joyful network card (8125->i226v), but this problem still exists. At the same time, VM2 is directly connected to a dual port 40G network card and running normally. I don't know how to troubleshoot the problem. Can someone help me?

1 hour ago, jasssssson said:

Hello everyone, I am currently installing a virtual machine on Unraid. The system I installed was debian12, and in order to connect a 4-port 2.5G network card directly, I selected one port to the virtual machine (VM1). However, when VM1 started and the installation went through network detection, the host restarted abnormally. I have tried security drivers and even tried using a Joyful network card (8125->i226v), but this problem still exists. At the same time, VM2 is directly connected to a dual port 40G network card and running normally. I don't know how to troubleshoot the problem. Can someone help me?

Is the 4 port card inuse by the host, maybe post diagnostics.

This is diagnostic information. I can see the network card in Unraid, and the virtual machine installation program also displays the name of the network card. However, when the progress bar is in progress, it restarts.
stream-diagnostics-20260126-1728.zip

I cannot see anything jumping out in the Diags. do you have any errors show on the console or do you have an external syslog setup. It may be there is an issue with the VM reset the card causing the host to have an issue.

It's like this, I modified the PCIe ACS and VFIO options in the VM Manager based on the messages on the forum, but it didn't help, so I restored the settings and restarted it once.

This is the file after I opened the virtual machine, installed and configured it, restarted abnormally , and downloaded diagnostics.

stream-diagnostics-20260126-1834.zip

Edited January 26Jan 26 by jasssssson

Need to have the info before the reboot as diags will not have the issues before the reboot. You need to setup a syslog server or look at the console wen it fails.

I tried to provide remote logging services on Synology, but I did not receive any abnormal data. There were no messages between the start of the logging server and the next restart.

Is there any other way to check the logs?

So does the whole host crash or just the VM? if you are not getting anything in the logs or on the console it will be difficult to find what is causing the crash if it whole host.

Let me rephrase the problem:

When I started the virtual machine with a direct network card (one of the 2.5G network card ports), I entered the installation program for debian12 and installed it normally until the network device detected it, the page froze, and the host (the host where Unraid was installed) restarted.

I tested again and used IPMI's remote control to monitor. From when I opened the virtual machine until the entire device was restarted, there was no output.

It is worth noting that if you do not install the debian program and remain stuck on the welcome page, you will not restart.

When restarting, IPMI remote will suddenly disconnect and there will be nothing.

So I reconnected a screen directly to the machine, and this is the video I recorded.