I have some VMs with minimum network speed of 1G
I need to connect each VM via a split tunnel.
While the raw speed between VMs are 1G but over the tunnels , the speed is down to 10% of the max speed (100M).
My question is that what and where are the bottlenecks?
I am expecting to see near 800M ~ 900M
Tests have been done using iperf3 and three VPN softwares
- SoftEther VPN (Dev version v5+)
- ocserv / openconnect
- wireguard
server
iperf3 --server --bind IP
client
iperf3 --client IP --time 1 --parallel 1
Raw ipv4 to ipv4 (from server A to server B)
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval Transfer Bitrate Retr
[ 5] 0.00-1.00 sec 1006 MBytes 8.44 Gbits/sec 1473 sender
[ 5] 0.00-1.04 sec 1002 MBytes 8.07 Gbits/sec receiver
SoftEther tap to tap (cascade connection from server A to sever B)
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval Transfer Bitrate Retr
[ 5] 0.00-1.00 sec 108 MBytes 899 Mbits/sec 1205 sender
[ 5] 0.00-1.05 sec 104 MBytes 833 Mbits/sec receiver
OpenConnect tun to tun (from server A to server B)
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval Transfer Bitrate Retr
[ 5] 0.00-1.00 sec 97.0 MBytes 814 Mbits/sec 5311 sender
[ 5] 0.00-1.04 sec 94.3 MBytes 759 Mbits/sec receiver
WireGuard
is twice faster near 200M
Both server Debian 11
and Kernel
Linux 206 5.10.0-23-amd64 #1 SMP Debian 5.10.179-2 (2023-07-14) x86_64 GNU/Linux
