7.4->8.1 Why did NIC devices change so radically... on ONE of two hosts?

[MrPete]

I have two almost identical host boxes (HP Z2 G5, with Intel I350 multi-port nic, etc. Nice )
They've been running great on 7.0 through 7.4
Time to upgrade to 8.1

Key item is NIC id's as I have a rich networking environment (pfSense HA, multiple VLANs, etc). Driver is igb...

One box went VERY smoothly. Same NIC device names as before (eg PCI igb 0000:03:00.0 becomes enp3s0f0)

The other? I tore my hair out, until I realized the device names have radically changed: igb 0000:03:00.0 becomes ens8191f0 ??!!!

What could cause this? Quite frustrating.

 

[shanreich]

This is a common occurrence when upgrading kernels, sadly.

 

[MrPete]

This is a common occurrence when upgrading kernels, sadly.

So it's semi-random whether the new device name is based on PCI location or BIOS ID? Grrr...

 

[spirit]

ask to the fucking systemd developpers

"stable" naming devices....until you upgrade your kernel, or systemd, or you add a new nvme pci device,...

personnaly, I have rollback to ethX naming, "net.ifnames=0 " in grub .

 

[ness1602]

yes unfortunately there are problems, even when you add lets say another pci-something, the naming changes,etc .etc.
Stable until proven guilty.

 

[MrPete]

@shanreich @spirit @ness1602 After MUCH hassle, I've learned a few things. The following is mostly documented at https://pve.proxmox.com/wiki/Network_Configuration

• This is all due to occasional "improvements" in "naming schemes." I could have avoided much hassle by setting a fixed naming scheme and/or simply setting fixed names for devices. Seems to me the latter would be an awesome option in the GUI! Just as valuable as the ability to set a fixed MAC address! Requires adding some config info to a file in /etc/systemd/network.

Pretty sure in my case the mess was caused by a virtual NUT (hwmon) device pointing to the same PCI location slipped in ahead of the real NIC. No idea how that happened but it caused havoc to me. Someone else can figure that out; I've torn out too much hair over this

I am not certain of the following, but it's the only thing that makes sense to me (and I've run out of time to more fully diagnose; my workaround is working...) If true, it feels like a bug...

• Going from 7.4 to 8.1 my pfSense VMs have NOT been happy connecting to network devices... until I cleared the fixed VM MAC and allowed the system to generate new ones.
• Which of course also meant inserting new MAC addresses into every static IP assignment.
• (I wonder if this relates to the newly renamed physical device names?)

(I hadn't thought about this in detail before now, but it's impossible to keep identical MAC addresses on VM network interfaces when cloning a VM, and (at least by default) when rebuilding from scratch. This is more than a little important when the VM includes a DNS server with static IP assignments (eg pfSense OPNsense etc)