Network interface name changes

[f4242]

Hello,

Yesterday, we did a regular PVE8 software upgrade (no major upgrade). Theses are the packages that were updated:

Install: proxmox-kernel-6.8.12-13-pve-signed:amd64 (6.8.12-13, automatic)
Upgrade: pve-docs:amd64 (8.4.0, 8.4.1), pve-edk2-firmware-ovmf:amd64 (4.2025.02-3, 4.2025.02-4~bpo12+1), proxmox-backup-restore-image:amd64 (0.6.1, 0.7.0), proxmox-widget-toolkit:amd64 (4.3.11, 4.3.13), pve-firmware:amd64 (3.15-4, 3.16-3), zfs-zed:amd64 (2.2.7-pve2, 2.2.8-pve1), zfs-initramfs:amd64 (2.2.7-pve2, 2.2.8-pve1), spl:amd64 (2.2.7-pve2, 2.2.8-pve1), pve-qemu-kvm:amd64 (9.2.0-6, 9.2.0-7), libnvpair3linux:amd64 (2.2.7-pve2, 2.2.8-pve1), proxmox-mail-forward:amd64 (0.3.2, 0.3.3), libpve-cluster-api-perl:amd64 (8.1.0, 8.1.2), pve-edk2-firmware-legacy:amd64 (4.2025.02-3, 4.2025.02-4~bpo12+1), libproxmox-backup-qemu0:amd64 (1.5.1, 1.5.2), libuutil3linux:amd64 (2.2.7-pve2, 2.2.8-pve1), libpve-storage-perl:amd64 (8.3.6, 8.3.7), libzpool5linux:amd64 (2.2.7-pve2, 2.2.8-pve1), proxmox-kernel-6.8:amd64 (6.8.12-11, 6.8.12-13), pve-cluster:amd64 (8.1.0, 8.1.2), proxmox-backup-file-restore:amd64 (3.4.1-1, 3.4.4-1), pve-container:amd64 (5.2.7, 5.3.0), pve-i18n:amd64 (3.4.4, 3.4.5), proxmox-archive-keyring:amd64 (3.2, 3.3), proxmox-backup-client:amd64 (3.4.1-1, 3.4.4-1), proxmox-mini-journalreader:amd64 (1.4.0, 1.5), pve-manager:amd64 (8.4.1, 8.4.11), libpve-common-perl:amd64 (8.3.2, 8.3.4), libpve-notify-perl:amd64 (8.1.0, 8.1.2), libzfs4linux:amd64 (2.2.7-pve2, 2.2.8-pve1), proxmox-kernel-helper:amd64 (8.1.1, 8.1.4), zfsutils-linux:amd64 (2.2.7-pve2, 2.2.8-pve1), libpve-cluster-perl:amd64 (8.1.0, 8.1.2), linux-libc-dev:amd64 (6.1.140-1, 6.1.147-1)
End-Date: 2025-08-18 18:04:14

Current pveversion: pve-manager/8.4.11/14a32011146091ed (running kernel: 6.8.12-13-pve)

The issue is that after reboot, there was no network working on the host. We found later that the eth0 interface has been renamed to eno1. We changed the network configuration and things worked again.

I understand this could happen on major update like PVE 7 to 8 or 8 to 9... but I wonder if this is normal to see a change like that on minor update?

 

[shanreich]

Yes, it can happen basically everytime the kernel / firmware gets updated.

 

[f4242]

This is not great that a breaking change like that occurs without warning when doing a minor update. This is the first time I see that on a Linux distribution.

 

[donhwyo]

You should be able to pin the interface names. https://translate.google.com/website?sl=auto&tl=en&hl=en&client=webapp&u=https://pve.proxmox.com/pve-docs/pve-admin-guide.html#network_override_device_names This seems to work on the latest pve8. I am trying it now.
Probably should be in the 8 to 9 script.

 

[damo2929]

this is fixable with persistent network naming that uses mac addresses and works with any linux distribution using systemd
add "net.ifname-policy=mac" to /etc/default/grub on GRUB_CMDLINE_LINUX line
update-grub
systemctl enable systemd-network-generator.service

if your systemd is new enough else

create the file needed manually

cat <<EOF > /etc/systemd/network/99-default.link
[Match]
OriginalName=*

[Link]
NamePolicy=mac
AlternativeNamesPolicy=database onboard slot path
MACAddressPolicy=none

EOF

as such after a reboot the nic will also be called after the mac address but with an enx prefix.