Proxmox 9 Upgrade Gone Wrong: One User’s Kernel Panic Nightmare

Upgrading your virtualization platform isn’t supposed to feel like walking into a minefield. But for one user, the leap from Proxmox VE 8 to 9 turned into a full-blown system meltdown — complete with a kernel panic and a maddening lack of clues. What was supposed to be a routine update spiraled into a troubleshooting rabbit hole involving a Realtek USB NIC, an AI accelerator in an NVMe slot, and some cryptic log messages (or lack thereof).

Here’s what went down, and why this story is sounding alarms in the homelab community.

The Setup Looked Solid… Until It Didn’t

The user, running under the handle unmesh59, kicked off the upgrade process by running pve8to9, the official script for jumping from Proxmox VE 8 to 9. They cleaned up nearly all warnings, save for a single note: dkms was still installed, and it was tied to a Realtek 2.5G USB NIC.

At this point, everything seemed stable. No red flags. No error explosions. Just your typical pre-reboot prep.

Then came the restart. And that’s where things went sideways.

“The system will not reboot now,” they wrote. “It can load the older 6.8.12 kernel but not the one that the upgrade installed.”