No network on boot. Manual start works correctly.

[pengu1n]

Hi. Bringing the question here as it seems networking-related.
https://forum.proxmox.com/threads/h...ng-nvme-and-upgrade-pve-from-7-4-to-8.138311/

The short of it seems like post upgrade, the bridge and/or the interface isn't started up upon boot. Manually seems fine.
Upgrade from 7.4 to 8.1 on baremetal. A new disk was added so devices numbering had to be adjusted.

Dmesg from console post boot I can see the port and bridge get to a disabled state at 20:55:46. Then a manual "#systemctl restart networking" brings them up, at 21:06 . This is me spending 5 minutes looking for errors in dmesg.

root@pve:~# dmesg -T | grep 'igc\|enp8s0\|vmbr0'
[Mon Dec 18 20:55:31 2023] igc 0000:08:00.0: PCIe PTM not supported by PCIe bus/controller
[Mon Dec 18 20:55:31 2023] igc 0000:08:00.0 (unnamed net_device) (uninitialized): PHC added
[Mon Dec 18 20:55:31 2023] igc 0000:08:00.0: 4.000 Gb/s available PCIe bandwidth (5.0 GT/s PCIe x1 link)
[Mon Dec 18 20:55:31 2023] igc 0000:08:00.0 eth0: MAC: f0:2f:74:1a:29:ee
[Mon Dec 18 20:55:34 2023] igc 0000:08:00.0 enp8s0: renamed from eth0
[Mon Dec 18 20:55:44 2023] vmbr0: port 1(enp8s0) entered blocking state
[Mon Dec 18 20:55:44 2023] vmbr0: port 1(enp8s0) entered disabled state
[Mon Dec 18 20:55:44 2023] igc 0000:08:00.0 enp8s0: entered allmulticast mode
[Mon Dec 18 20:55:44 2023] igc 0000:08:00.0 enp8s0: entered promiscuous mode
[Mon Dec 18 20:55:46 2023] igc 0000:08:00.0 enp8s0: PHC removed
[Mon Dec 18 20:55:46 2023] vmbr0: port 1(enp8s0) entered disabled state
[Mon Dec 18 20:55:46 2023] igc 0000:08:00.0 enp8s0 (unregistering): left allmulticast mode
[Mon Dec 18 20:55:46 2023] igc 0000:08:00.0 enp8s0 (unregistering): left promiscuous mode
[Mon Dec 18 20:55:46 2023] vmbr0: port 1(enp8s0) entered disabled state
[Mon Dec 18 20:55:46 2023] igc 0000:08:00.0: PCIe PTM not supported by PCIe bus/controller
[Mon Dec 18 20:55:46 2023] igc 0000:08:00.0 (unnamed net_device) (uninitialized): PHC added
[Mon Dec 18 20:55:46 2023] igc 0000:08:00.0: 4.000 Gb/s available PCIe bandwidth (5.0 GT/s PCIe x1 link)
[Mon Dec 18 20:55:46 2023] igc 0000:08:00.0 eth0: MAC: f0:2f:74:1a:29:ee
[Mon Dec 18 20:55:46 2023] igc 0000:08:00.0 enp8s0: renamed from eth0
[Mon Dec 18 21:06:39 2023] vmbr0: port 1(enp8s0) entered blocking state
[Mon Dec 18 21:06:39 2023] vmbr0: port 1(enp8s0) entered disabled state
[Mon Dec 18 21:06:39 2023] igc 0000:08:00.0 enp8s0: entered allmulticast mode
[Mon Dec 18 21:06:39 2023] igc 0000:08:00.0 enp8s0: entered promiscuous mode
[Mon Dec 18 21:06:43 2023] igc 0000:08:00.0 enp8s0: NIC Link is Up 1000 Mbps Full Duplex, Flow Control: RX
[Mon Dec 18 21:06:43 2023] vmbr0: port 1(enp8s0) entered blocking state
[Mon Dec 18 21:06:43 2023] vmbr0: port 1(enp8s0) entered forwarding state

What can it be, and more importantly how can I attempt to fix please?

root@pve:~# cat /etc/network/interfaces
auto lo
iface lo inet loopback

auto enp8s0
iface enp8s0 inet manual

auto vmbr0
iface vmbr0 inet static
        address 192.168.5.2/24
        gateway 192.168.5.1
        bridge-ports enp8s0
        bridge-stp off
        bridge-fd 0