NIC issues after fresh install


New Member
Feb 24, 2019
Attempted a 5.3 fresh bare metal install from usb yesterday morning. The installation seemed to go fine except that one of my two intel nics didn't work properly. One is onboard and the other is pcie. During install I selected the onboard as the management interface and that interface worked fine, got it configured, all good. I could access the web gui, etc. The other nic appeared to just die or more like turned itself off because the h/w was seen by proxmox but there was no connection to the switch (connection lights off).

I checked cables, etc and no matter what I did, that second nic would not light up (again, even though the device was seen by proxmox). By the third hour of troubleshooting, I had restless people in the house dying for internet access and media access so I had to bail out, go back to xen and restore all the vms from backup. Once I rebooted to the xen install media, the 2nd nic lit back up immediately (with the original cables, new cables, etc). Restored the xen env and both nics working fine.

After I ended the family "emergency" by getting everyone's internet restored, I got to thinking that maybe proxmox disables nics that aren't explicitly configured during install? And maybe had I just setup a 2nd bridge and added that nic to it, it would have lit up? Or am I way off? I'd like to give this another shot next weekend, but looking for some feedback on what I may want to try.
So the expected behaviour is that all nics other than the one chosen for management are disabled such that the physical connection is dead/disabled? On this second nic, the activity lights on the card and the switch port just died when I installed proxmox. It was like the card had died or the cable was unplugged (though it never was until I started troubleshooting).

If that's the expected behaviour, that should be explicitly mentioned in the docs. I spent way too much time trying to get that nic to light up before even trying to configure proxmox figuring I had no chance of getting things working until I could get that second nic to light up. :) I didn't even get a chance to config proxmox before bailing out because I figured I had a problem with that second nic.
Well, it is hard to check the status of your NIC without the system up and running. You could check the output of `dmesg`, `ip link` and/or `ethtool` for a start.


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