Bandwidth issue for VMs - PVE as a router/fw

Hi,

Weird behavior for a Ubuntu Server 24.04 VM.

Download speed ~500 kbps

While a debian 12 VM is able to download at full speed 1000 Mbps.

On PVE host no bandwidth issue, firewall on (nftables), masquarade, ipv4 forwarding activated.

VMs use CPU type = host with numa activated as well.

Seems that this only occurs when we use PVE as a router/fw for VMs. If PVE is not forwarding VM traffic, no pb so far.

On Windows machines, CPU type = host (numa) - download performance is 10 times...

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