I've a very confusing problem with my setup:
Server: Debian 9.3 with OpenVPN 2.4.0
Client: Win 7 VirtualBox VM on Win 10 Host with OpenVPN 2.4.4
The tunnel is very unstable. Sometimes downloads break down to 0 bit/s for a few seconds, sometimes completely.
I did some tests with iperf. The max. speed between client and server outside of the tunnel is around 85MBit/s up and down. That's okay. Speed within the tunnel is bad with max. 2 MBit/s. But more interessting is this (iperf -R on the client, output on the server side):
Code: Select all
Accepted connection from 10.8.0.6, port 51959
[ 5] local 10.8.0.1 port 5201 connected to 10.8.0.6 port 51960
[ ID] Interval Transfer Bandwidth Retr Cwnd
[ 5] 0.00-1.00 sec 76.9 KBytes 629 Kbits/sec 1 1.33 KBytes
[ 5] 1.00-2.00 sec 0.00 Bytes 0.00 bits/sec 1 2.65 KBytes
[ 5] 2.00-3.00 sec 0.00 Bytes 0.00 bits/sec 0 13.3 KBytes
[ 5] 3.00-4.00 sec 0.00 Bytes 0.00 bits/sec 0 14.6 KBytes
[ 5] 4.00-5.00 sec 0.00 Bytes 0.00 bits/sec 0 14.6 KBytes
[ 5] 5.00-6.00 sec 0.00 Bytes 0.00 bits/sec 0 15.9 KBytes
[ 5] 6.00-7.00 sec 0.00 Bytes 0.00 bits/sec 0 15.9 KBytes
[ 5] 7.00-8.00 sec 0.00 Bytes 0.00 bits/sec 0 17.2 KBytes
[ 5] 8.00-9.00 sec 368 KBytes 3.02 Mbits/sec 38 2.65 KBytes
[ 5] 9.00-10.00 sec 211 KBytes 1.73 Mbits/sec 24 2.65 KBytes
[ 5] 10.00-11.00 sec 362 KBytes 2.96 Mbits/sec 31 5.30 KBytes
[ 5] 11.00-12.00 sec 262 KBytes 2.15 Mbits/sec 21 5.30 KBytes
[ 5] 12.00-13.00 sec 260 KBytes 2.13 Mbits/sec 20 2.65 KBytes
[ 5] 13.00-14.00 sec 200 KBytes 1.64 Mbits/sec 24 7.95 KBytes
[ 5] 14.00-15.00 sec 266 KBytes 2.18 Mbits/sec 17 5.30 KBytes
[ 5] 15.00-16.00 sec 297 KBytes 2.43 Mbits/sec 25 2.65 KBytes
[ 5] 16.00-17.00 sec 262 KBytes 2.15 Mbits/sec 20 6.63 KBytes
[ 5] 17.00-18.00 sec 264 KBytes 2.16 Mbits/sec 20 3.98 KBytes
[ 5] 18.00-18.31 sec 87.5 KBytes 2.35 Mbits/sec 4 6.63 KBytes
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval Transfer Bandwidth Retr
[ 5] 0.00-18.31 sec 2.85 MBytes 1.31 Mbits/sec 246 sender
[ 5] 0.00-18.31 sec 0.00 Bytes 0.00 bits/sec receiver
Any idea how I could find the cause for that?