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    IPSEC VTI tunnels lost packets

    Scheduled Pinned Locked Moved IPsec
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    • B
      bbrendon
      last edited by

      I'm a bit confused because in my pfSense it shows "Routed (VTI)". There is no routed & VTI option.

      Also, VTI has been problematic since day 1. It is now much better but we still have problems with it on occasion where the only solution seems to be a reboot.

      Maybe check Async Crypto setting and make sure it's unchecked?

      Sorry I know none of this is specific to your exact issue.

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      • J
        Jose Carlos S @pete35
        last edited by

        @pete35 Thanks you, but ICMP packets normaly has 64 k size... are too far of mtu limit, are you agree? And MTU problems shoud be -always-, I mean either it always works (make it the same package size) or it never works, don't you agree? and the problem is that there is a packet loss, completely random.

        If I remember correctly, the packet size limitation is a global limit in the IPSEC configuration and that if it were configured wrong with a P2 in "Tunnel" mode it should give the same problem.

        Thanks for your help.

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        • J
          Jose Carlos S @bbrendon
          last edited by

          @bbrendon Yes you are right, when it said routed it meant tunnel mode. I am with you in that P2 with VTI have always given problems, but offer many advantages, we want to configure it to activate OSPF and the truth is that it is something that seems that it has not yet been worked on. For example, when you restart the pfsense with VTI tunnels it takes a lot because in the boot process it configures the VTI interfaces before the rest of the interfaces and consequently before the IPSEC and it is something that I do not quite understand, really.

          We are going to deactivate the async crypto and tell you how we have done.

          Thanks for your help.

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          • P
            pete35
            last edited by

            It may be a dpinger problem. You may try to disable monitoring and transfer some real data and look for transfer problems.

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

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            • J
              Jose Carlos S @pete35
              last edited by

              @pete35 Manual ping inside VTI tunnel (from console)

              PING 10.0.0.6 (10.0.0.6) from 10.0.0.5: 56 data bytes
              64 bytes from 10.0.0.6: icmp_seq=0 ttl=64 time=8.693 ms
              64 bytes from 10.0.0.6: icmp_seq=1 ttl=64 time=9.009 ms
              64 bytes from 10.0.0.6: icmp_seq=2 ttl=64 time=8.533 ms
              64 bytes from 10.0.0.6: icmp_seq=3 ttl=64 time=8.127 ms
              64 bytes from 10.0.0.6: icmp_seq=4 ttl=64 time=8.372 ms
              64 bytes from 10.0.0.6: icmp_seq=5 ttl=64 time=7.789 ms
              64 bytes from 10.0.0.6: icmp_seq=6 ttl=64 time=9.185 ms
              64 bytes from 10.0.0.6: icmp_seq=7 ttl=64 time=9.128 ms
              64 bytes from 10.0.0.6: icmp_seq=8 ttl=64 time=8.564 ms
              64 bytes from 10.0.0.6: icmp_seq=9 ttl=64 time=8.986 ms
              64 bytes from 10.0.0.6: icmp_seq=10 ttl=64 time=8.397 ms
              64 bytes from 10.0.0.6: icmp_seq=11 ttl=64 time=8.365 ms
              64 bytes from 10.0.0.6: icmp_seq=12 ttl=64 time=8.565 ms
              64 bytes from 10.0.0.6: icmp_seq=13 ttl=64 time=8.018 ms
              64 bytes from 10.0.0.6: icmp_seq=14 ttl=64 time=8.314 ms
              64 bytes from 10.0.0.6: icmp_seq=15 ttl=64 time=8.468 ms
              64 bytes from 10.0.0.6: icmp_seq=16 ttl=64 time=7.918 ms
              64 bytes from 10.0.0.6: icmp_seq=40 ttl=64 time=8.476 ms
              64 bytes from 10.0.0.6: icmp_seq=42 ttl=64 time=8.745 ms
              64 bytes from 10.0.0.6: icmp_seq=44 ttl=64 time=9.085 ms
              64 bytes from 10.0.0.6: icmp_seq=45 ttl=64 time=8.446 ms
              64 bytes from 10.0.0.6: icmp_seq=46 ttl=64 time=8.421 ms
              64 bytes from 10.0.0.6: icmp_seq=47 ttl=64 time=7.987 ms
              64 bytes from 10.0.0.6: icmp_seq=48 ttl=64 time=8.730 ms
              64 bytes from 10.0.0.6: icmp_seq=49 ttl=64 time=8.659 ms
              64 bytes from 10.0.0.6: icmp_seq=50 ttl=64 time=7.910 ms
              64 bytes from 10.0.0.6: icmp_seq=51 ttl=64 time=8.086 ms
              64 bytes from 10.0.0.6: icmp_seq=52 ttl=64 time=8.591 ms
              64 bytes from 10.0.0.6: icmp_seq=53 ttl=64 time=8.262 ms
              64 bytes from 10.0.0.6: icmp_seq=54 ttl=64 time=8.945 ms
              64 bytes from 10.0.0.6: icmp_seq=55 ttl=64 time=9.079 ms
              64 bytes from 10.0.0.6: icmp_seq=56 ttl=64 time=9.513 ms
              64 bytes from 10.0.0.6: icmp_seq=57 ttl=64 time=9.241 ms
              64 bytes from 10.0.0.6: icmp_seq=58 ttl=64 time=8.343 ms
              64 bytes from 10.0.0.6: icmp_seq=65 ttl=64 time=8.575 ms
              64 bytes from 10.0.0.6: icmp_seq=66 ttl=64 time=7.544 ms
              64 bytes from 10.0.0.6: icmp_seq=67 ttl=64 time=7.647 ms
              64 bytes from 10.0.0.6: icmp_seq=69 ttl=64 time=8.109 ms
              64 bytes from 10.0.0.6: icmp_seq=70 ttl=64 time=8.974 ms
              64 bytes from 10.0.0.6: icmp_seq=71 ttl=64 time=8.377 ms
              64 bytes from 10.0.0.6: icmp_seq=72 ttl=64 time=8.489 ms
              64 bytes from 10.0.0.6: icmp_seq=73 ttl=64 time=8.321 ms
              64 bytes from 10.0.0.6: icmp_seq=74 ttl=64 time=8.157 ms
              64 bytes from 10.0.0.6: icmp_seq=75 ttl=64 time=8.351 ms
              64 bytes from 10.0.0.6: icmp_seq=76 ttl=64 time=7.531 ms

              As you can see from the sequence number packets are lost.

              But if you look at the latency of the previous packet and the later packet they are very similar, so I can assume that, rather than packet loss, there is packet discarding ...

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              • P
                pete35
                last edited by

                Have you checked these:

                'Disable hardware checksum offload',
                'Disable hardware TCP segmentation offload'
                'Disable hardware large receive offload'

                all of them should be checked.

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

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                • J
                  Jose Carlos S @pete35
                  last edited by

                  @pete35 Yes, everywhere

                  Captura de pantalla 2020-10-30 a las 17.08.26.png

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                  • P
                    pete35
                    last edited by pete35

                    The packet loss in the ping log is for about 14 seconds... You disabled DPD ( try to configure it) .... is the tunnel renewed in that time ? Do you see multiple SA child entries for the tunnel at this time?

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

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                    • J
                      Jose Carlos S @pete35
                      last edited by

                      @pete35 Hi, we have also activated the DPD and we have the same problem.

                      As you know multiple SA child its "too normal" but sometime with P2 tunnel type we usualy view multiple SA childs.

                      Captura de pantalla 2020-10-30 a las 18.01.38.png

                      But, how can we fix this?

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                      • J
                        Jose Carlos S @pete35
                        last edited by

                        @pete35 Timeouts:
                        P1 28800
                        P2 3600

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                        • P
                          pete35
                          last edited by

                          It may be, that that frequent ( some seconds) rekeying causes packet loss.

                          You need to reconfigure the rekey/reauth parameters to overcome that:

                          Side 1: IKEv2, Rekey configured, Reauth disabled, child SA close action set to restart/reconnect
                          Side 2: IKEv2, Rekey configured, Reauth disabled, responder only set, child SA close action left at default (clear)

                          look at this: https://redmine.pfsense.org/issues/10176

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

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                          • P
                            pete35
                            last edited by

                            You wrote that you want to implement ospf with that vti tunnels. Be aware, that there are multiple issues with the ospf integration in pfsense. If you have less than 50 routes, the efforts to implement this isnt worth the outcome. And on top, there is no smooth sailing after that, because there are frequent interrupts in data traffic depending on instable tunnels, even on redundant routes.

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

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                            • J
                              Jose Carlos S @pete35
                              last edited by

                              @pete35 Hi Pete, I have applied the parameters that you have commented and, for now, it continues to lose packages.

                              Anyway, if it was a renegotiation problem it would happen every 3600 seconds, right? and the graph we have of loss is "practically" constant, don't you think?

                              Look at the timeline

                              Captura de pantalla 2020-10-30 a las 18.45.46.png

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                              • J
                                Jose Carlos S @pete35
                                last edited by

                                @pete35 I agree, this is the reason why I am looking for link stability, because if not implementing OSPF over unstable links, it might be the closest thing to hell...

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                                • P
                                  pete35
                                  last edited by

                                  The timemarks on your multiple sa's is showing a reinstall /rekey every 20 seconds. 3600 seconds would be fine, but it doesnt do that. Please check your SA situation again.

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

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                                  • P
                                    pete35
                                    last edited by

                                    About OSPF, not only unstable links are causing interrupts, even simple adding or removing a route is causing an interrupt in the whole OSPF system, all pfsense routing devices will renew their routing table per restart ... , not only the OSPF routes will dissappear also any other routes in tne routing table. Interrupt time depends on settings but around 30 seconds is quite usual. If your applications can survive that, you are lucky.

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

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                                    • J
                                      Jose Carlos S @pete35
                                      last edited by

                                      @pete35 Perfect

                                      Captura de pantalla 2020-10-30 a las 19.35.16.png

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                                      • J
                                        Jose Carlos S @pete35
                                        last edited by

                                        @pete35 Yes, this is a issue, our intention, to minimize these situations is to increase the number of areas and play with death times and execution timeouts in order to minimize this problems.

                                        The main objective of the project is to offer high availability between two IPSEC tunnels, what we would like to do is have one IPSEC on WAN1 and another IPSEC (with the same destination) on WAN2. There are more reasons why we would like to implement dynamic routes, but it could be a separate topic.

                                        Do you recommend another solution?

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                                        • P
                                          pete35
                                          last edited by

                                          If you want HA with multiwan you may look for Gatewaygroups with a usually straightforward painless implementation. But this only works with a low number of routes. How many sites do you have?

                                          Is the packetloss gone now? If not, you may post all your detailed configurations for the two sites, to check again all the parameters.

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

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                                          • J
                                            Jose Carlos S @pete35
                                            last edited by

                                            @pete35 Hi Pete, we are looking for, more than a multiwan solution, a high availability IPSEC solution. Another option that we are evaluating is to put P2 VTIs and configurate gateway groups within the routes that go within the VTIs.

                                            Schema:

                                            Captura de pantalla 2020-10-30 a las 21.31.19.png

                                            To the previous scheme you have to add 2 WANs for each site and in each site there are 2 Pfsense in HA. The main problem is that they want point-to-point connection between all the sites and we want to avoid it with some intermediate jump.

                                            On the other hand, the tunnel maintains the same level of packet loss, although we have improved regarding the stability of the SAs

                                            P1 Configuration
                                            Captura de pantalla 2020-10-30 a las 21.43.23.png

                                            P2 Configuration
                                            Captura de pantalla 2020-10-30 a las 21.42.46.png

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