Coming from 6.12.10 - everything was working fine, but after upgrading to 6.12.14 I lost network.  No hardware changes. 

 

My AsRockRack E3C246D4U motherboard has 2 onboard LAN ethernet NICs which are both disabled in BIOS. I have a Mellanox ConnectX-3 EN (MCX311A-XCAT) 10Gbe PCIe NIC installed (single port) which is what unraid should be using for network.  However, in 6.12.14, Unraid has assigned eth0 to some USB NIC device I've never heard of called "CDC Ethernet Device" while it assigns my Mellanox NIC to eth1.  (Screenshot from IPMI KVM below)

 

In the previous OS version (6.12.10), the Mellanox 10Gbe NIC is automatically assigned to eth0 and the virtual USB NIC device is disabled:

 

There is definitely no physical USB ethernet adapters connected to the server.  Maybe this is a red herring, but my best guess is that this is a virtual device that is there for IPMI KVM redirection purposes??  I found a support thread from another user mentioning the same type of "cdc_ether" device and for them it ended up being related to their Dell iDRAC (Dell's IPMI implementation) "OS TO IDRAC PASS THROUGH" feature, which they disabled and that fixed their problem.  I have looked all through the BMC Settings in the BIOS as well as in AsRockRack's HTML5 IPMI KVM tool and I can't find anything relating to USB NIC pass-through (there is pass-through settings but only for virtual floppy/optical/harddisk).  

 

There is no network-rules.cfg file in /boot/config and therefore no Interface Rules section in Network Settings in the GUI so I am unable to manually assign the Mellanox 10Gbe NIC to eth0.  I tried to rename /boot/config/network.cfg and reboot, but this didn't fix it.  In Network Settings, I tried to disable bonding and bridging on the eth0 USB NIC and reboot but that didn't work either.  I then rolled back to 6.12.10 and everything was working again.  

 

I have attached Diagnostics.  Appreciate any assistance!

 

tower-diagnostics-20241209-1158.zip

Likely the IPMI NIC, was just going to link that same post.

 

You can try blacklisting that USB driver.

 

 

 

 

 

 

Appreciate the response/suggestion @JorgeB!  I am not sure how to do that but I will look into it. 

 

I noticed in 6.10.12 the same cdc_ether device get registered to usb0:

Quote

Dec  8 18:37:52 Tower kernel: cdc_ether 1-8.2:2.0 usb0: register 'cdc_ether' at usb-0000:00:14.0-8.2, CDC Ethernet Device, e6:d9:05:17:6d:a0

 

while in 6.10.14 it gets registered to eth0:

Quote

Dec  9 11:46:11 Tower kernel: cdc_ether 1-8.2:2.0 eth0: register 'cdc_ether' at usb-0000:00:14.0-8.2, CDC Ethernet Device, e6:d9:05:17:6d:a0

 

Seems like something has changed with the kernel or drivers that results in the same device being recognized/registered differently in 6.10.12 vs 6.10.14. 

 

Does this seem like something that I should file a bug report for so that an official fix could maybe be implemented?

 

Edited December 9, 20241 yr by tallguydirk

I decided to try going from 6.12.10 to 6.12.11 and was able to do so and get an IP automatically.  Then I went from 6.12.11 to 6.12.13 and again was able to get an IP automatically.  Then I went from 6.12.13 to 6.12.14 and have the same problem described in this thread.  So the problem is definitely something with 6.12.14.

Decided to create a bug report so if anyone has input please post there instead...mods feel free to delete this.