I installed OMV 5.X on the ASRock X570D4U motherboard (the one without 10 GbE NICS). It has a dual NIC INTEL i210 ethernet controller.
Everything works out-of-the-box. But my network speed is slow, transferring a file has a speed around 25 MB/s - 35 MB/s. I tested directly between a laptop and the motherboard via a cross-cable, same issue occurs.
If I ping (also via cross-cable), then I get a response around 1.5ms - 2.5ms.
I use only one port, so aggregation is not configured. The box has static IP address set.
Via ethtool I see that the connection speed is set to 1000 Mb/s.
It is a plain installation, not yet plug-ins activated.
I installed Windows on the same motherboard, then I see a response of <= 1ms. Also the file transfer is around 80-90 MB/s.
Can someone give me some pointers to look for?