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    IPSec is very slow between two pfsense routers

    Scheduled Pinned Locked Moved IPsec
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    • keyserK
      keyser Rebel Alliance @patrick.pesegodinski
      last edited by

      @patrick-pesegodinski I know this sounds like BS, but you need to try and benchmark the VPN connection with something other than SMB. SMB is NOTORIOUSLY bad on “less than 1500 bytes” MTU links like a VPN. It’s all over the place if any fragmentation is involved.
      So try and clamp down your MSS and benchmark it with a iPerf3 TCP test.

      Love the no fuss of using the official appliances :-)

      P 1 Reply Last reply Reply Quote 0
      • P
        patrick.pesegodinski @keyser
        last edited by

        @keyser I understand your thinking, but with OpenVPN I get transfer rates 10x higher than IPSEC.

        keyserK 1 Reply Last reply Reply Quote 0
        • keyserK
          keyser Rebel Alliance @patrick.pesegodinski
          last edited by

          @patrick-pesegodinski i know, and thats likely because OpenVPN knows how to participate in MTU Discovery so the SMB Client knows the proper packet sizes to use.
          IPSec VPN on pfsense does not play Nice in this Area - it’s a known bug and has been for years, But unfortunately IPSec VPN sees Very little developer love, so we have to work around it.
          Thats why we need MSS clamping and an iPerf3 test - then we really know where the culprit is buried.

          Love the no fuss of using the official appliances :-)

          P M 2 Replies Last reply Reply Quote 1
          • P
            patrick.pesegodinski @keyser
            last edited by

            @keyser hello friend.

            The test iperf

            Connecting to host 172.29.0.1, port 5201
            [ 5] local 10.0.0.1 port 45903 connected to 172.29.0.1 port 5201
            [ ID] Interval Transfer Bitrate Retr Cwnd
            [ 5] 0.00-1.00 sec 26.3 MBytes 221 Mbits/sec 19 64.1 KBytes
            [ 5] 1.00-2.00 sec 27.1 MBytes 227 Mbits/sec 15 61.8 KBytes
            [ 5] 2.00-3.00 sec 26.7 MBytes 224 Mbits/sec 15 82.0 KBytes
            [ 5] 3.00-4.00 sec 27.1 MBytes 228 Mbits/sec 28 57.6 KBytes
            [ 5] 4.00-5.00 sec 26.1 MBytes 219 Mbits/sec 16 71.2 KBytes
            [ 5] 5.00-6.00 sec 26.6 MBytes 224 Mbits/sec 19 67.0 KBytes
            [ 5] 6.00-7.00 sec 27.1 MBytes 227 Mbits/sec 15 27.4 KBytes
            [ 5] 7.00-8.00 sec 26.5 MBytes 223 Mbits/sec 36 68.6 KBytes
            [ 5] 8.00-9.00 sec 26.8 MBytes 225 Mbits/sec 18 81.6 KBytes
            [ 5] 9.00-10.00 sec 21.0 MBytes 176 Mbits/sec 67 81.7 KBytes


            [ ID] Interval Transfer Bitrate Retr
            [ 5] 0.00-10.00 sec 261 MBytes 219 Mbits/sec 248 sender
            [ 5] 0.00-10.00 sec 261 MBytes 219 Mbits/sec receiver

            iperf Done.

            keyserK 1 Reply Last reply Reply Quote 0
            • keyserK
              keyser Rebel Alliance @patrick.pesegodinski
              last edited by

              @patrick-pesegodinski Is this before or after clamping down MSS?
              You are seeing 220mbit which is around 25MB/s (Half your OpenVPN throughput). But I cannot see if you tried a single session iPerf or the default with multiple parallel streams.

              Love the no fuss of using the official appliances :-)

              P 1 Reply Last reply Reply Quote 0
              • P
                patrick.pesegodinski @keyser
                last edited by

                @keyser Test performed without changing the MSS.
                I used the iperf client in Pfsense itself with the default settings.

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                • M
                  michmoor LAYER 8 Rebel Alliance @patrick.pesegodinski
                  last edited by

                  @patrick-pesegodinski

                  Post your iPerf syntax here so we can understand what you are doing.
                  Something along the lines of

                  iperf3 -c 192.168.70.26 -P 50 -t 30
                  

                  Also post for us the before MSS change and after MSS change results.

                  Firewall: NetGate,Palo Alto-VM,Juniper SRX
                  Routing: Juniper, Arista, Cisco
                  Switching: Juniper, Arista, Cisco
                  Wireless: Unifi, Aruba IAP
                  JNCIP,CCNP Enterprise

                  P 1 Reply Last reply Reply Quote 0
                  • M
                    michmoor LAYER 8 Rebel Alliance @keyser
                    last edited by

                    @keyser
                    I found something in redmine for MTU suggestions.

                    https://redmine.pfsense.org/issues/14508

                    Firewall: NetGate,Palo Alto-VM,Juniper SRX
                    Routing: Juniper, Arista, Cisco
                    Switching: Juniper, Arista, Cisco
                    Wireless: Unifi, Aruba IAP
                    JNCIP,CCNP Enterprise

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                    • P
                      patrick.pesegodinski @michmoor
                      last edited by

                      @michmoor Excuse my ignorance, but I'm not familiar with iperf. Which fields do I need to adjust?

                      5466484c-126b-4694-8621-f314189cc88b-image.png

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                      • M
                        michmoor LAYER 8 Rebel Alliance @patrick.pesegodinski
                        last edited by

                        @patrick-pesegodinski
                        do not use iperf on the firewall.
                        use iperf between your clients (sitting behind your firewall).

                        Firewall: NetGate,Palo Alto-VM,Juniper SRX
                        Routing: Juniper, Arista, Cisco
                        Switching: Juniper, Arista, Cisco
                        Wireless: Unifi, Aruba IAP
                        JNCIP,CCNP Enterprise

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                        • P
                          patrick.pesegodinski @michmoor
                          last edited by

                          @michmoor 1f121d95-5939-4faa-a741-3386bf11b08d-TESTE.txt

                          The test with MSS standard.

                          1 Reply Last reply Reply Quote 0
                          • N
                            NOCling
                            last edited by

                            https://packetpushers.net/ipsec-bandwidth-overhead-using-aes/
                            Best MSS for IPsec tunnel Model 1328, if you use transport Mode and a 1500 WAN line, you can use 1372.

                            Netgate 6100 & Netgate 2100

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                            • P
                              patrick.pesegodinski @NOCling
                              last edited by

                              @NOCling hello friend.

                              Thanks for helping me. Your information about MSS with 1328 solved my problem.

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                              • iulianteodorI
                                iulianteodor
                                last edited by iulianteodor

                                What should be the average IPSec VPN speed between two pfsense with 1Gb NIC interface and 1Gbps internet?
                                I've seen all kinds of comments on different forums that the speed could be higher, but I can't do more than that:

                                alt text

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                                • O
                                  optimusprime @patrick.pesegodinski
                                  last edited by

                                  @patrick-pesegodinski Did you Apply MSS on WAN interface settings and does it need to be same on both sides of tunnel ?

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                                  • P
                                    patrick.pesegodinski @optimusprime
                                    last edited by

                                    @optimusprime I apply in this option:

                                    d15f6b0e-dc4f-4612-9973-a628ee43d373-image.png

                                    8d1c5b5b-af44-4ef6-aa5f-1b5f3cfd3100-image.png

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