Slow Speed with SoftEther VPN

[Vince.pan]

I built a softether vpn server in the proxmox virtual machine, using both Debian 10 and CentOS7

I used "ip link set ens18 promisc on" in the VM to turn promisc on
The device can connect to this VPN but the network speed is very slow

My network environment is 100Mbps downlink 30Mbps uplink
I have tested L2TP and Openvpn, the downlink speed is about 1Mbps, and the uplink speed is 20Mbps
At first I thought it was the bridged network of the virtual machine that caused the problem. So I pass through a network port to the virtual machine directly, but the speed did not improve
I also tested Bridge and SecureNAT, not work
But I did not encounter this problem on another computer (Arch Linux) and Raspberry Pi (Rasbian)

NEED HELP!

 

[Dominic]

A first step would be to determine the maximum speed between the different machines (for example, between PVE host and VM) in your network using a tool like iperf3.