Intel I226-V NICs enp5s0 / enp7s0 showing PHC removed and disappearing after PVE 8.4 → 9.1 upgrade

satfan

New Member
Feb 4, 2026
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Hello,


I have a 6-port Intel I226-V machine. After upgrading from PVE 8.4 to 9.1, two network interfaces enp5s0 and enp7s0 are detected during boot but disappear later from the system.


The kernel boot log shows all 6 NICs are correctly named by the igc driver:

plaintext





[ 1.706602] igc 0000:01:00.0 enp1s0: renamed from eth0<br>[ 1.707101] igc 0000:02:00.0 enp2s0: renamed from eth1<br>[ 1.707841] igc 0000:04:00.0 enp4s0: renamed from eth3<br>[ 1.708763] igc 0000:07:00.0 enp7s0: renamed from eth5<br>[ 1.711823] igc 0000:03:00.0 enp3s0: renamed from eth2<br>[ 1.712250] igc 0000:05:00.0 enp5s0: renamed from eth4<br>



But shortly after boot, I get these two lines (PHC removed):

plaintext





[ 11.850910] igc 0000:07:00.0 enp7s0: PHC removed<br>[ 12.050203] igc 0000:05:00.0 enp5s0: PHC removed<br>



After that, enp5s0 and enp7s0 are completely gone from:


  • ip link
  • ls /sys/class/net
  • nmcli
  • Proxmox GUI network list (except hardware info)


The other 4 ports work normally. All 6 ports worked perfectly in PVE 8.4.


I have tried:


  • modprobe -r igc &amp;&amp; modprobe igc
  • update-initramfs -u -k all
  • upgrade to latest pve-kernel
  • disable Secure Boot
  • check no udev rules deleting interfaces
  • check lspci: all 6 I226-V controllers still present


This appears to be an igc driver issue in PVE 9.1 kernel where some Intel I226-V ports are removed with PHC removed.


Does anyone know how to prevent PHC removed and keep all NICs online?

Thanks for any help.
 
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