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    I can ping both directions but only access servers one way...?

    IPsec
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    • G
      Gblenn @viragomann
      last edited by Gblenn

      @viragomann I tried various settings but no difference that I can see...

      I did some PCAP when trying to access Site C from Site A and this is what it looks like in pfsense.
      The problem is the same regardless of which server I'm trying to acces, be it pfsense itself or in this case a switch. I just chose it for simplicity and cleanliness of the pcap.

      2a907b40-9a3c-4995-986b-d4d692166a0b-image.png

      And the downloaded file from within Wireshark

      108daa83-9ca0-40a5-ac50-0eacace78c52-image.png

      If i google pfsense blocking SYN on port 80/443 I find an old redmine issue that clearly has been resolved since way back? So it must be something different, or? Why do I not see this in the 2.7.2 setup?

      I should add that in the firewall log I see a PASS on the IPSec interface of 10.10.2.3:PORT to 10.10.177.5:80
      31e288be-acdb-4aef-8388-972b4b5b195a-image.png

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      • V
        viragomann @Gblenn
        last edited by

        @Gblenn
        Are the routes set properly at C?

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        • G
          Gblenn @viragomann
          last edited by

          @viragomann Yes, site C being the pfsense side, the only thing to do there is to set the static route 172.168.1.0/24 to the IPSecVTI Gateway that was automagically created.

          32c84c45-f5fb-44aa-acc1-84269e7a8809-image.png

          On Sophos it looks pretty similar and it's been quite obvious when setting this up a few times that whenever I forgot this part, I don't get near where I am now...

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          • G
            Gblenn @Gblenn
            last edited by

            I have been trying to go through the logs in Sophos as well and everything I can find on that side shows green as in all packets are passed by the correct fw and nat rules for this.

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            • G
              Gblenn @Gblenn
              last edited by

              When trying to log in via SSH on a Linux machine on Site C , I get the following...
              Simlar to before but it looks like there is a response initally from 192.168.1.31?

              cadb9ec4-5d8f-45ea-a4be-6f9971facb9a-image.png

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                viragomann @Gblenn
                last edited by viragomann

                @Gblenn
                So even if the destination machine was sending an ACK, the SYN packet is re-transmitted.

                I'd suspect, that the ACK packet does not arrive at the machine, which initiated the connection. But why?

                BTW: I noticed, that the LAN at A is a public network range.
                However, this shouldn't matter if the routes are added properly.

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                • G
                  Gblenn @viragomann
                  last edited by Gblenn

                  @viragomann said in I can ping both directions but only access servers one way...?:

                  @Gblenn
                  So even if the destination machine was sending an ACK, the SYN packet is re-transmitted.

                  It appears that way doesn't it... however having run the same test again several times I don't see the ACK coming back. So perhaps it was an anomaly?

                  I'd suspect, that the ACK packet does not arrive at the machine, which initiated the connection. But why?

                  BTW: I noticed, that the LAN at A is a public network range.
                  However, this shouldn't matter if the routes are added properly.

                  Ah you are right, it is in the public IP range... I made the simplest possible change from 192 to 172 and I should have changed to 16 as well. But I don't suppose pfsense would care? And it's working towards site B anyway...

                  I started thinking there was some sync issue since site A and C are connected via a switch. Site A is for testing purposes at the moment. But latency is below 1 ms when pinging between them. So I added a limiter in order to add a bit of latency to get it closer to what I have between the other sites, but that doesn't seem to change things.

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                  • G
                    Gblenn @Gblenn
                    last edited by

                    I have sort of given up on getting this to work, for now at least. Ended up deploying Wireguard on a VM on the Sophos LAN and have a connection going that way instead...

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                    • G
                      Gblenn @Gblenn
                      last edited by Gblenn

                      @viragomann
                      So this is definitely a 24.03 thing since a change to 2.7.2 solved the issue immediately... No change in the configuration on either side, just a switch to CE.
                      And I guess I have to see if the patches I just found out about for IPsec VTI will fix the issue.

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                      • G
                        Gblenn @Gblenn
                        last edited by

                        And now it's working also on 24.03 after implementing patches for Redmine #15449, #15430 and #15606...

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                        • V
                          viragomann @Gblenn
                          last edited by

                          @Gblenn
                          Great info. Thanks.
                          I never had this issue, even running multiple IPSec site-to-site connections to other routers than pfSense and didn't apply IPSec patches.

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                            Gblenn @viragomann
                            last edited by

                            @viragomann Well, first time I have used IPSec since Sophos doesn't do WG...

                            One thing to note though, this is Routed VTI connection, which is different from "Tunnel IPv4" that you have as default Mode in pfsense...

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                              viragomann @Gblenn
                              last edited by

                              @Gblenn
                              Ah ya, you mentioned above.
                              I never set up a VTI to be honest, I just have some small knowledge about from the docs.

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                              • G
                                Gblenn @viragomann
                                last edited by

                                @viragomann Well, since I couldn't get the default one to work, I tried VTI and it worked. Not sure what I did wrong with the other method but I did find VTI a bit more like the WG tunnels I have set up in the past. With the gateway and routing settings at least...

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