Weird networking issues with VirtI/O

[apollo13]

Hi there, I will try my best to describe the issue and maybe it is not even a proxmox bug, but I am not sure where to start. I have reduced our problem to the following: We have a vmbr0 to has a bond2 as member and bonds two interfaces from an Intel 10Gigabit X550T network card. The bond members go to one 10 Gbit switch and as fallback to a 1 Gbit switch. So far so good, this does work. No we do have one problem that only seems to show itself when using FreeBSD (PfSense to be exact).

When the connection fails over to the 1 Gbit link, connections to the PfSense VM on that host start hanging when accessed from other VMs on that same host (kinda randomly, sometimes a 200MB download works but most often it starts hanging at a random download percentage). Please note that the connection between does VMs does not leave the Host at all and connections between 2 Linux VMs on the host work just fine. If I remove the bond from the configuration and readd the problematic interface as single bridge member all is well again.

Do you have any ideas where I should start looking? Is this a virtio driver Bug in PfSense? vmxnet3 exhibits no issues but limits me to gigabit speeds even on the same host.

I can provide any details wanted, I simply do not know what information to provide currently :/

 

[apollo13]

Okay, moving the backup connection to another network card in the server fixed the problem. No idea… but good enough as a workaround