Navigation

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

    Does pfsense/freebsd filter the "session id"?

    Firewalling
    4
    14
    4700
    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.
    • A
      avel last edited by

      hello!

      i have a strange question here from a customer of us, who has some of
      his employees working in our office for some time.
      From our office they want to connect to their cisco vpn service,
      but it is only possible for one of them at the same time. At the moment the
      second employee tries to connect, the server refuses to talk to him,
      because he can't distinguish between both connections, therefore
      treading them as the same (we have a fixed external ip as usual).

      Our customer told us that this problem is on our side, and it is
      happening because: "our firewall is not forwarding the session-id"
      and "this could have something to with your NAT settings…"

      We have a typical configuration with doing NAT automatically
      and let "Lan -> any, any" so i can't figure out where i should
      have disallowed that. Also i am not sure at all, what exactly
      he meant by "session-id"... the usual problem, i can't reach
      him until next week and the project is urgent... i suppose
      something inside the TCP-Header or vpn stuff that gets
      filtered, but is freebsd/pfsense doing that?

      Is someone there who could identify what the actual
      problem could be and if i can fix it on our side with pfsense?
      Is it possible that NAT throws this "session id" away? And if so,
      can i fix this somehow?

      many thanks
      Avel

      1 Reply Last reply Reply Quote 0
      • A
        aldo last edited by

        not really your problem ther is only one ip proberly only one person can connect.
        because it does not differentiate.

        get more ips on your wan and send them out differnet ones????
        make a tunnel between the two sites.

        1 Reply Last reply Reply Quote 0
        • A
          avel last edited by

          thanks for replying.

          Well, they claim that it would work on other offices were also only one
          fix ip-adress for outside connections is available… so they tend to
          be sure that it is our problem.

          A site-to-site is not possible, since the policy of the customer
          does not allow that anymore (big company, you know...).

          Any other idea? Can it be NAT?

          1 Reply Last reply Reply Quote 0
          • C
            cmb last edited by

            I've had 3-4 simultaneous client machines connected to the same Cisco VPN device before.

            I'm guessing they must not have NAT-T enabled on their end. It works fine with that.

            1 Reply Last reply Reply Quote 0
            • A
              avel last edited by

              thanks for the answer.

              Ok, but if their configuration works for other supporting companies
              and since you can confirm that these kind of connections do work at all,
              the problem must be on our side.

              What could it be? We only got some inbound-NAT rules, but
              i don't think they have anything to do with it, as said, the
              firewall rules are just "LAN -> any", and we do automatic NAT
              from LAN to internet.

              1 Reply Last reply Reply Quote 0
              • C
                cmb last edited by

                what pfsense version are you running?

                1 Reply Last reply Reply Quote 0
                • A
                  avel last edited by

                  pfSense 1.0.1 RELEASE

                  1 Reply Last reply Reply Quote 0
                  • C
                    cmb last edited by

                    Well, shouldn't matter, one of the machines I go through to get to the Internet is a 1.0-RC version.

                    Do you have advanced outbound NAT enabled?

                    1 Reply Last reply Reply Quote 0
                    • A
                      avel last edited by

                      no, "advanced outbound NAT " is disabled.
                      I have "Enable IPSec passthru" aktivated.

                      1 Reply Last reply Reply Quote 0
                      • S
                        sullrich last edited by

                        Upgrade to a recent testing snapshot: http://snapshots.pfsense.com/FreeBSD6/RELENG_1_2/updates/

                        1 Reply Last reply Reply Quote 0
                        • C
                          cmb last edited by

                          I seriously doubt if a snapshot is going to change anything, but I would try it.

                          There are some IPsec passthrough changes, though I don't think it will matter because I'm running behind way older versions than what you are and don't have problems.

                          1 Reply Last reply Reply Quote 0
                          • C
                            cmb last edited by

                            Something just hit me. Looking back at the subject, "session ID", that's not IPsec related (AFAIK). Is this by chance a PPTP or L2TP connection? We (or at least I) hear Cisco and assume IPsec.

                            1 Reply Last reply Reply Quote 0
                            • A
                              avel last edited by

                              i assume they use IPSec yes, but i have forwarded the question to be sure.
                              I will post the answer as soon as i get it.

                              1 Reply Last reply Reply Quote 0
                              • A
                                avel last edited by

                                ok i got an answer:

                                "…this is a common problem we do encounter with many routers that are not Cisco/AVM,
                                the address translation of IPSec is not handled correctly, therfore our gateway can't
                                differentiate between the incomming connections..."

                                So it's IPSec. Any ideas?

                                1 Reply Last reply Reply Quote 0
                                • First post
                                  Last post