We have 2 proxmox servers utilizing the connectx-5 cards attached to a qnmap switch(trunk) at 25G. Recently these server lost connectivity to the management network we believe due to a proxmox upgrade. After lots of troubleshooting it was found that if promiscuous mode was turned on (interface or bridge) the connectivity was restored. All firmware on the server and card was upgraded to try resolving this issue. Filtering was adjust with no luck:
ethtool -K ens17f0np0 rx-vlan-filter off
ethtool -K ens17f0np0 rx-vlan-offload off
The only thing that seem to restore connectivity is:
ip link set dev ens17f0np0 promisc on
Other proxmox servers with same card attached to the same switch operate fine, but have not been updated. Any insights?