Netgate Discussion Forum
    • Categories
    • Recent
    • Tags
    • Popular
    • Users
    • Search
    • Register
    • Login

    Poor performace with Openvpn

    Scheduled Pinned Locked Moved OpenVPN
    29 Posts 4 Posters 2.9k Views 4 Watching
    Loading More Posts
    • Oldest to Newest
    • Newest to Oldest
    • Most Votes
    Reply
    • Reply as topic
    Log in to reply
    This topic has been deleted. Only users with topic management privileges can see it.
    • 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?

      1 Reply Last reply Reply Quote 0
      • 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

        T 1 Reply Last reply Reply Quote 0
        • 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?

          1 Reply Last reply Reply Quote 0
          • 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

            1 Reply Last reply Reply Quote 0
            • 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.

              1 Reply Last reply Reply Quote 0
              • 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

                1 Reply Last reply Reply Quote 0
                • 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>

                    T 1 Reply Last reply Reply Quote 0
                    • 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

                      1 Reply Last reply Reply Quote 0
                      • 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>

                          T 1 Reply Last reply Reply Quote 0
                          • 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

                            1 Reply Last reply Reply Quote 0
                            • 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

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

                                            Did you disable NCP? Otherwise it will still be negotiating those.

                                            But as I said this looks like some sort of mtu/fragmenting issue. Run a packet capture and see what's happening.

                                            Steve

                                            T 1 Reply Last reply Reply Quote 0
                                            • First post
                                              Last post
                                            Copyright 2025 Rubicon Communications LLC (Netgate). All rights reserved.