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    Poor performace with Openvpn

    Scheduled Pinned Locked Moved OpenVPN
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    • stephenw10S Offline
      stephenw10 Netgate Administrator
      last edited by

      Try testing iperf3 between the sites outside the tunnel. And/or speedtest inside the tunnel. You cannot compare the two tests directly, especially with only one stream in iperf. Try using, say, 4 with -P 4

      Steve

      T 1 Reply Last reply Reply Quote 1
      • T Offline
        trumee @stephenw10
        last edited by trumee

        @stephenw10 I did both tests as you suggested.

        This is a test of iperf3 outside the tunnel. It shows line speeds.

        Site A to public IP SiteB

        $ iperf3 -c SiteB
        Connecting to host SiteB, port 5201
        [  5] local 172.16.9.21 port 47024 connected to SiteB port 5201
        [ ID] Interval           Transfer     Bitrate         Retr  Cwnd
        [  5]   0.00-1.00   sec  15.0 MBytes   126 Mbits/sec    0   2.02 MBytes       
        [  5]   1.00-2.00   sec  17.5 MBytes   147 Mbits/sec    0   2.90 MBytes       
        [  5]   2.00-3.00   sec  17.5 MBytes   147 Mbits/sec  661   1.52 MBytes       
        [  5]   3.00-4.00   sec  17.5 MBytes   147 Mbits/sec    0   1.61 MBytes       
        [  5]   4.00-5.00   sec  17.5 MBytes   147 Mbits/sec    0   1.68 MBytes       
        [  5]   5.00-6.00   sec  17.5 MBytes   147 Mbits/sec    0   1.72 MBytes       
        [  5]   6.00-7.00   sec  17.5 MBytes   147 Mbits/sec    0   1.76 MBytes       
        [  5]   7.00-8.00   sec  17.5 MBytes   147 Mbits/sec    1   1.26 MBytes       
        [  5]   8.00-9.00   sec  17.5 MBytes   147 Mbits/sec    0   1.35 MBytes       
        [  5]   9.00-10.00  sec  17.5 MBytes   147 Mbits/sec    2   1017 KBytes       
        - - - - - - - - - - - - - - - - - - - - - - - - -
        [ ID] Interval           Transfer     Bitrate         Retr
        [  5]   0.00-10.00  sec   172 MBytes   145 Mbits/sec  664             sender
        [  5]   0.00-10.06  sec   171 MBytes   142 Mbits/sec                  receiver
        
        iperf Done.
        

        Site A to public IP SiteB in reverse

        $ iperf3 -c SiteB -R
        Connecting to host SiteB, port 5201
        Reverse mode, remote host SiteB is sending
        [  5] local 172.16.9.21 port 47042 connected to SiteB port 5201
        [ ID] Interval           Transfer     Bitrate
        [  5]   0.00-1.00   sec  13.3 MBytes   111 Mbits/sec                  
        [  5]   1.00-2.00   sec  17.7 MBytes   148 Mbits/sec                  
        [  5]   2.00-3.00   sec  17.7 MBytes   148 Mbits/sec                  
        [  5]   3.00-4.00   sec  17.7 MBytes   149 Mbits/sec                  
        [  5]   4.00-5.00   sec  17.7 MBytes   148 Mbits/sec                  
        [  5]   5.00-6.00   sec  17.7 MBytes   148 Mbits/sec                  
        [  5]   6.00-7.00   sec  17.7 MBytes   148 Mbits/sec                  
        [  5]   7.00-8.00   sec  17.7 MBytes   148 Mbits/sec                  
        [  5]   8.00-9.00   sec  17.7 MBytes   148 Mbits/sec                  
        [  5]   9.00-10.00  sec  17.7 MBytes   148 Mbits/sec                  
        - - - - - - - - - - - - - - - - - - - - - - - - -
        [ ID] Interval           Transfer     Bitrate         Retr
        [  5]   0.00-10.05  sec   175 MBytes   146 Mbits/sec    0             sender
        [  5]   0.00-10.00  sec   172 MBytes   145 Mbits/sec                  receiver
        
        iperf Done.
        

        Next is speedtest inside the tunnel. Here was seed again that the Download speed (which is equivalent to Reverse in iperf3) is poor compared to upload.

        alt text

        Also ran iperf3 -P4, but the results were the same as before.
        Is the bottleneck in SiteA router or SiteB router?

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        • stephenw10S Offline
          stephenw10 Netgate Administrator
          last edited by

          Hmm, much faster with the speedtest result over VPN though. Using 4 streams really made no difference?

          Is there a much smaller window size in one direction?

          Steve

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          • T Offline
            trumee @stephenw10
            last edited by

            @stephenw10

            This is the speed i get with 4 streams in the reverse direction. There is some improvement in speed (14 mbps to 23 mbps).

            [ ID] Interval           Transfer     Bitrate         Retr
            [  5]   0.00-10.05  sec  9.12 MBytes  7.61 Mbits/sec   26             sender
            [  5]   0.00-10.00  sec  8.91 MBytes  7.47 Mbits/sec                  receiver
            [  7]   0.00-10.05  sec  6.31 MBytes  5.27 Mbits/sec   39             sender
            [  7]   0.00-10.00  sec  6.20 MBytes  5.20 Mbits/sec                  receiver
            [  9]   0.00-10.05  sec  6.31 MBytes  5.27 Mbits/sec   58             sender
            [  9]   0.00-10.00  sec  6.20 MBytes  5.20 Mbits/sec                  receiver
            [ 11]   0.00-10.05  sec  6.55 MBytes  5.47 Mbits/sec   29             sender
            [ 11]   0.00-10.00  sec  6.38 MBytes  5.35 Mbits/sec                  receiver
            [SUM]   0.00-10.05  sec  28.3 MBytes  23.6 Mbits/sec  152             sender
            [SUM]   0.00-10.00  sec  27.7 MBytes  23.2 Mbits/sec                  receiver
            

            What do you mean by window size and how do i check?

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            • stephenw10S Offline
              stephenw10 Netgate Administrator
              last edited by

              The 'Cwnd' column in iperf. It only shows it at the end sending so you need to check both.

              But you can see it's much larger outside the tunnel. You might need mss-fix to prevent fragmentation.

              Steve

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              • T Offline
                trumee
                last edited by trumee

                I followed this article to get the value for mssfix.

                $ping -M do -s 1470  SiteB
                PING SiteB 1470(1498) bytes of data.
                ping: local error: message too long, mtu=1492
                ping: local error: message too long, mtu=1492
                ping: local error: message too long, mtu=1492
                
                $ ping -M do -s 1464  -c 1 SiteB
                PING SiteB 1464(1492) bytes of data.
                1468 bytes from SiteB: icmp_seq=1 ttl=55 time=51.5 ms
                
                

                According to the article mssfix = mtu-40, so i used mssfix 1424 in the client config of SiteB. Further following this article, i subtracted 28 from the MTU and set link-mtu to 1436.

                So finally the config looks so,

                $cat /var/etc/openvpn/client2.conf
                dev ovpnc2
                verb 1
                dev-type tun
                dev-node /dev/tun2
                writepid /var/run/openvpn_client2.pid
                #user nobody
                #group nobody
                script-security 3
                daemon
                keepalive 10 60
                ping-timer-rem
                persist-tun
                persist-key
                proto udp4
                cipher AES-256-CBC
                auth SHA256
                up /usr/local/sbin/ovpn-linkup
                down /usr/local/sbin/ovpn-linkdown
                local myip
                engine cryptodev
                tls-client
                client
                lport 0
                management /var/etc/openvpn/client2.sock unix
                remote SiteA 1194
                ifconfig 10.8.9.2 10.8.9.1
                auth-user-pass /var/etc/openvpn/client2.up
                auth-retry nointeract
                route 172.16.1.0 255.255.255.0
                route 172.16.9.0 255.255.255.0
                ca /var/etc/openvpn/client2.ca 
                cert /var/etc/openvpn/client2.cert 
                key /var/etc/openvpn/client2.key 
                tls-auth /var/etc/openvpn/client2.tls-auth 1
                ncp-ciphers AES-128-GCM:AES-256-GCM
                compress lz4-v2
                resolv-retry infinite
                topology subnet
                mssfix 1424
                link-mtu 1436
                

                With the above config i get following result in the reverse.

                $iperf3 -s
                Accepted connection from 172.16.9.21, port 35516
                [  5] local 192.168.1.111 port 5201 connected to 172.16.9.21 port 35518
                [ ID] Interval           Transfer     Bitrate         Retr  Cwnd
                [  5]   0.00-1.00   sec   416 KBytes  3.41 Mbits/sec    0   30.9 KBytes       
                [  5]   1.00-2.00   sec  1.09 MBytes  9.16 Mbits/sec    0   78.6 KBytes       
                [  5]   2.00-3.00   sec  2.71 MBytes  22.8 Mbits/sec    0    201 KBytes       
                [  5]   3.00-4.00   sec  2.26 MBytes  19.0 Mbits/sec   20    112 KBytes       
                [  5]   4.00-5.00   sec  2.22 MBytes  18.6 Mbits/sec    0    121 KBytes       
                [  5]   5.00-6.00   sec  2.47 MBytes  20.7 Mbits/sec    0    135 KBytes       
                [  5]   6.00-7.00   sec  2.71 MBytes  22.7 Mbits/sec    0    149 KBytes       
                [  5]   7.00-8.00   sec  2.96 MBytes  24.8 Mbits/sec    0    162 KBytes       
                [  5]   8.00-9.00   sec  3.21 MBytes  26.9 Mbits/sec    0    175 KBytes       
                [  5]   9.00-10.00  sec  3.45 MBytes  29.0 Mbits/sec    0    189 KBytes       
                [  5]  10.00-10.05  sec   252 KBytes  41.2 Mbits/sec    0    189 KBytes       
                - - - - - - - - - - - - - - - - - - - - - - - - -
                [ ID] Interval           Transfer     Bitrate         Retr
                [  5]   0.00-10.05  sec  23.7 MBytes  19.8 Mbits/sec   20             sender
                -----------------------------------------------------------
                Server listening on 5201
                -----------------------------------------------------------
                

                So it hasnt improved the speed.

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                • stephenw10S Offline
                  stephenw10 Netgate Administrator
                  last edited by

                  Hmm the window size is tiny though.

                  I would run a packet capture of the iperf traffic over the tunnel and see what's happening there, is it still fragmenting.

                  You can test it by setting the window and mss size in the iperf client.

                  Steve

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                  • P Offline
                    pete35
                    last edited by

                    Hmmm, even the performance isnt symetrical, it is way to low.

                    What are the crypto settings of this tunnel ? Is AESNI used? Did you check the tunnel IPv4 settings? What version of Pfsense is that on both sites? Are this the standard Nic of the boards? With the newer OVPN versions, there are some additional buffer Settings , did you use that? Anything other on that connection?

                    <a href="https://carsonlam.ca">bintang88</a>
                    <a href="https://carsonlam.ca">slot88</a>

                    P 1 Reply Last reply Reply Quote 0
                    • P Offline
                      pete35 @pete35
                      last edited by

                      What is the value of cryptographic settings in Advanced- Miscellaneous? It should be "aes-ni" on both sites... and inside the tunnel configuration ... "none" ...

                      <a href="https://carsonlam.ca">bintang88</a>
                      <a href="https://carsonlam.ca">slot88</a>

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                      • stephenw10S Offline
                        stephenw10 Netgate Administrator
                        last edited by

                        Even without AES-NI it should be faster with that hardware.

                        It is possible to incorrectly use the crypto framework which can actually reduce throughput. OpenSSL will use AES-NI if the CPU has it.

                        But even with that 30Mbps is far lower than expected.

                        Steve

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                        • T Offline
                          trumee @pete35
                          last edited by

                          @pete35 said in Poor performace with Openvpn:

                          What is the value of cryptographic settings in Advanced- Miscellaneous? It should be "aes-ni" on both sites... and inside the tunnel configuration ... "none" ...

                          These are the crypto settings on both sides, https://imgur.com/a/Qzar59q

                          P 1 Reply Last reply Reply Quote 0
                          • P Offline
                            pete35 @trumee
                            last edited by

                            @trumee

                            pls remove all configurations, where "cryptodev" is included and set it to aesni only.

                            <a href="https://carsonlam.ca">bintang88</a>
                            <a href="https://carsonlam.ca">slot88</a>

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                            • T Offline
                              trumee @pete35
                              last edited by trumee

                              @pete35 said in Poor performace with Openvpn:

                              @trumee

                              pls remove all configurations, where "cryptodev" is included and set it to aesni only.

                              I have enabled AESNI in Advanced-Miscellaneous. In the tunnel configuration, should the 'Hardware Crypto' be set to 'No Hardware Crypto Acceleration'?

                              alt text

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                              • RicoR Offline
                                Rico LAYER 8 Rebel Alliance
                                last edited by

                                Yes.

                                -Rico

                                1 Reply Last reply Reply Quote 0
                                • stephenw10S Offline
                                  stephenw10 Netgate Administrator
                                  last edited by

                                  Set it to no-hardware crypto there.

                                  It will be interesting to see if that makes any measurable difference. The speeds you're seeing seem to be less than anything I would expect to be affected by that.

                                  Steve

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                                  • T Offline
                                    trumee
                                    last edited by

                                    I set it to 'No Hardware Crypto'. It did not make a difference.

                                    [  5] local 192.168.1.111 port 5201 connected to 192.16.9.21 port 33160
                                    [ ID] Interval           Transfer     Bitrate         Retr  Cwnd
                                    [  5]   0.00-1.00   sec  1.74 MBytes  14.6 Mbits/sec    2   92.3 KBytes       
                                    [  5]   1.00-2.00   sec  1.87 MBytes  15.7 Mbits/sec    0    109 KBytes       
                                    [  5]   2.00-3.00   sec  2.05 MBytes  17.2 Mbits/sec    0    117 KBytes       
                                    [  5]   3.00-4.00   sec  2.24 MBytes  18.8 Mbits/sec    0    125 KBytes       
                                    [  5]   4.00-5.00   sec  2.43 MBytes  20.3 Mbits/sec    0    138 KBytes       
                                    [  5]   5.00-6.00   sec  2.30 MBytes  19.3 Mbits/sec    3    110 KBytes       
                                    [  5]   6.00-7.00   sec  2.24 MBytes  18.8 Mbits/sec    0    131 KBytes       
                                    [  5]   7.00-8.00   sec  1.99 MBytes  16.7 Mbits/sec   12   71.5 KBytes       
                                    [  5]   8.00-9.00   sec  1.49 MBytes  12.5 Mbits/sec    0   81.9 KBytes       
                                    [  5]   9.00-10.00  sec  1.49 MBytes  12.5 Mbits/sec    0   94.9 KBytes       
                                    [  5]  10.00-10.05  sec   191 KBytes  29.6 Mbits/sec    0   96.2 KBytes       
                                    - - - - - - - - - - - - - - - - - - - - - - - - -
                                    [ ID] Interval           Transfer     Bitrate         Retr
                                    [  5]   0.00-10.05  sec  20.0 MBytes  16.7 Mbits/sec   17             sender
                                    -----------------------------------------------------------
                                    Server listening on 5201
                                    -----------------------------------------------------------
                                    
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                                    • RicoR Offline
                                      Rico LAYER 8 Rebel Alliance
                                      last edited by

                                      Please share all your OpenVPN settings.
                                      What is your Encryption Algorithm?
                                      With GCM I have seen OpenVPN traffic beyond 400 MBit/s
                                      My SG-5100 can easy do ~250 MBit/s

                                      -Rico

                                      T 1 Reply Last reply Reply Quote 0
                                      • RicoR Offline
                                        Rico LAYER 8 Rebel Alliance
                                        last edited by

                                        For testing...could you set the Encryption Algorithm to None? Just to rule this out...

                                        -Rico

                                        T 1 Reply Last reply Reply Quote 0
                                        • T Offline
                                          trumee @Rico
                                          last edited by trumee

                                          @Rico I am using 'cipher AES-256-CBC', 'auth SHA256' and ncp-ciphers 'AES-256-GCM:AES-128-GCM'. The server side VPN config is the following and the client side config is posted above.

                                          $less /var/etc/openvpn/server1.conf
                                          dev ovpns1
                                          verb 1
                                          dev-type tun
                                          dev-node /dev/tun1
                                          writepid /var/run/openvpn_server1.pid
                                          #user nobody
                                          #group nobody
                                          script-security 3
                                          daemon
                                          keepalive 10 60
                                          ping-timer-rem
                                          persist-tun
                                          persist-key
                                          proto udp4
                                          cipher AES-256-CBC
                                          auth SHA256
                                          up /usr/local/sbin/ovpn-linkup
                                          down /usr/local/sbin/ovpn-linkdown
                                          local 127.0.0.1
                                          tls-server
                                          server 10.8.9.0 255.255.255.0
                                          client-config-dir /var/etc/openvpn-csc/server1
                                          ifconfig 10.8.9.1 10.8.9.2
                                          tls-verify "/usr/local/sbin/ovpn_auth_verify tls 'VoipVPNServer' 1"
                                          lport 1194
                                          management /var/etc/openvpn/server1.sock unix
                                          route 192.168.0.0 255.255.255.0
                                          route 192.168.1.0 255.255.255.0
                                          route 192.168.2.0 255.255.255.0
                                          route 192.168.5.0 255.255.255.0
                                          route 192.168.6.0 255.255.255.0
                                          route 192.168.10.0 255.255.255.0
                                          route 192.168.18.0 255.255.255.0
                                          route 192.168.40.0 255.255.255.0
                                          route 192.168.50.0 255.255.255.0
                                          ca /var/etc/openvpn/server1.ca 
                                          cert /var/etc/openvpn/server1.cert 
                                          key /var/etc/openvpn/server1.key 
                                          dh /etc/dh-parameters.2048
                                          crl-verify /var/etc/openvpn/server1.crl-verify 
                                          tls-auth /var/etc/openvpn/server1.tls-auth 0
                                          ncp-ciphers AES-256-GCM:AES-128-GCM
                                          compress lz4-v2
                                          persist-remote-ip
                                          float
                                          topology subnet
                                          
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                                          • T Offline
                                            trumee @Rico
                                            last edited by

                                            @Rico said in Poor performace with Openvpn:

                                            For testing...could you set the Encryption Algorithm to None? Just to rule this out...

                                            -Rico

                                            There is no change to the result,

                                            $ iperf3 -c 192.168.1.111 -R
                                            Connecting to host 192.168.1.111, port 5201
                                            Reverse mode, remote host 192.168.1.111 is sending
                                            [  5] local 172.16.9.21 port 33962 connected to 192.168.1.111 port 5201
                                            [ ID] Interval           Transfer     Bitrate
                                            [  5]   0.00-1.00   sec  1.21 MBytes  10.2 Mbits/sec                  
                                            [  5]   1.00-2.00   sec  1.61 MBytes  13.5 Mbits/sec                  
                                            [  5]   2.00-3.00   sec   905 KBytes  7.41 Mbits/sec                  
                                            [  5]   3.00-4.00   sec  1.01 MBytes  8.48 Mbits/sec                  
                                            [  5]   4.00-5.00   sec   538 KBytes  4.41 Mbits/sec                  
                                            [  5]   5.00-6.00   sec   753 KBytes  6.17 Mbits/sec                  
                                            [  5]   6.00-7.00   sec   987 KBytes  8.09 Mbits/sec                  
                                            [  5]   7.00-8.00   sec  1.18 MBytes  9.88 Mbits/sec                  
                                            [  5]   8.00-9.00   sec  1.43 MBytes  12.0 Mbits/sec                  
                                            [  5]   9.00-10.00  sec  1.65 MBytes  13.9 Mbits/sec                  
                                            - - - - - - - - - - - - - - - - - - - - - - - - -
                                            [ ID] Interval           Transfer     Bitrate         Retr
                                            [  5]   0.00-10.05  sec  11.6 MBytes  9.67 Mbits/sec  150             sender
                                            [  5]   0.00-10.00  sec  11.2 MBytes  9.40 Mbits/sec                  receiver
                                            
                                            iperf Done.
                                            
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