iPerf testing slow OVPN speeds
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- I have two sites connected using OVPN. Main office & remote office,
- Both sites have 100/100 fibre connections. tested and confirmed.
- User have been complaining of slow speeds over the VPN
If I test the connections directly with iPerf, bypassing the VPN, I have discovered the following.
When using the main office as the server and the remote office as the client I often receive results where receiver speed of half of the sender speed. See below:
Connecting to host 124.19.X.X, port 5201 [ 5] local 59.154.X.X port 44899 connected to 124.19.X.X port 5201 [ ID] Interval Transfer Bitrate Retr Cwnd [ 5] 0.00-1.00 sec 11.2 MBytes 93.9 Mbits/sec 0 144 KBytes [ 5] 1.00-2.00 sec 11.1 MBytes 93.4 Mbits/sec 0 144 KBytes [ 5] 2.00-3.00 sec 11.1 MBytes 93.4 Mbits/sec 0 144 KBytes [ 5] 3.00-4.00 sec 11.2 MBytes 94.0 Mbits/sec 0 144 KBytes [ 5] 4.00-5.00 sec 11.2 MBytes 94.1 Mbits/sec 0 144 KBytes [ 5] 5.00-6.00 sec 11.3 MBytes 94.4 Mbits/sec 0 144 KBytes [ 5] 6.00-7.00 sec 11.3 MBytes 94.5 Mbits/sec 0 144 KBytes [ 5] 7.00-8.00 sec 11.2 MBytes 94.2 Mbits/sec 0 144 KBytes [ 5] 8.00-9.00 sec 11.3 MBytes 94.5 Mbits/sec 0 144 KBytes [ 5] 9.00-10.00 sec 11.3 MBytes 94.7 Mbits/sec 0 144 KBytes - - - - - - - - - - - - - - - - - - - - - - - - - [ ID] Interval Transfer Bitrate Retr [ 5] 0.00-10.00 sec 112 MBytes 94.1 Mbits/sec 0 sender [ 5] 0.00-20.03 sec 112 MBytes 47.0 Mbits/sec receiver iperf Done.When I swap this around and use the remote office as the server and the main office as the client I mostly receive results where both the sender and receiver speeds are equal but with retries. See below:
Connecting to host 59.154.X.X, port 5201 [ 5] local 124.19.X.X port 19494 connected to 59.154.X.X port 5201 [ ID] Interval Transfer Bitrate Retr Cwnd [ 5] 0.00-1.01 sec 8.91 MBytes 74.2 Mbits/sec 17 180 KBytes [ 5] 1.01-2.00 sec 9.10 MBytes 76.9 Mbits/sec 18 86.0 KBytes [ 5] 2.00-3.00 sec 10.9 MBytes 91.6 Mbits/sec 21 75.1 KBytes [ 5] 3.00-4.00 sec 4.98 MBytes 41.7 Mbits/sec 9 47.7 KBytes [ 5] 4.00-5.00 sec 10.2 MBytes 85.2 Mbits/sec 14 80.8 KBytes [ 5] 5.00-6.00 sec 10.9 MBytes 91.7 Mbits/sec 14 103 KBytes [ 5] 6.00-7.00 sec 9.95 MBytes 83.4 Mbits/sec 15 103 KBytes [ 5] 7.00-8.00 sec 9.91 MBytes 83.1 Mbits/sec 22 62.5 KBytes [ 5] 8.00-9.00 sec 10.4 MBytes 87.5 Mbits/sec 14 83.2 KBytes [ 5] 9.00-10.00 sec 10.0 MBytes 83.9 Mbits/sec 15 86.7 KBytes - - - - - - - - - - - - - - - - - - - - - - - - - [ ID] Interval Transfer Bitrate Retr [ 5] 0.00-10.00 sec 95.3 MBytes 79.9 Mbits/sec 159 sender [ 5] 0.00-10.01 sec 95.1 MBytes 79.7 Mbits/sec receiver iperf Done.Does this indicate an issue with the fibre connection at the main office?
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