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    VLAN 2 VLAN TCP traffic drops after 30 seconds

    Scheduled Pinned Locked Moved Routing and Multi WAN
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    • T Offline
      tpit
      last edited by

      Dear Community,

      On a customers 3100, 21.05-RELEASE, we have an issue when the customer is accessing his switches through telnet or ssh.

      Setup
      vlan switches 10.2.0.0/24
      vlan data 192.168.50.0/24

      Gateway of those subnets is the 3100 for both. Upon connecting to the switch it works but then the connection gets dropped after 30 seconds or so. The state shows:
      VLAN2 tcp 192.168.50.103:57179 -> 10.2.0.100:22 SYN_SENT:CLOSED 9 / 0 2 KiB / 0 B

      And then the connection drops.

      Interface for both the subnets to "live" on is the mvneta1 interface where both vlans are tagged upon.

      Not sure where to go from here. From my searches here in the forum and online I found multiple assymetric routing issues to be the underlying issue. However, this traffic does not egress from the firewall over multiple wans nor has it got anything to do with nat.

      Would be great to get your thoughts on the matter. I have remote access and I can send whatever else you might need for more info.

      Cheers,
      Tommie

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      • johnpozJ Offline
        johnpoz LAYER 8 Global Moderator @tpit
        last edited by

        @tpit said in VLAN 2 VLAN TCP traffic drops after 30 seconds:

        However, this traffic does not egress from the firewall over multiple wans nor has it got anything to do with nat.

        That doesn't mean its not asymmetrical.

        A drawing including where the switches set, do the switches have svi in both vlans?

        So say you talk to switch 10.20.0.100 from 192.168.50.103, but the switch answers via the interface it has in 192.168.50, then yeah pfsense never sees the return traffic and would close the state after the timeout.

        An intelligent man is sometimes forced to be drunk to spend time with his fools
        If you get confused: Listen to the Music Play
        Please don't Chat/PM me for help, unless mod related
        SG-4860 25.07 | Lab VMs 2.8, 25.07

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        • T Offline
          tpit @johnpoz
          last edited by

          @johnpoz said in VLAN 2 VLAN TCP traffic drops after 30 seconds:

          192.168.50.103, but the switch answers via the interface it has in 192.168.50, then yeah pfsense never sees the return traffic and would close the state after the

          That would make tons of sense... not sure why I haven't checked this at all! Let me investigate if he gave his switch multiple IPv4 in each vlan!!! Be right back.

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          • T Offline
            tpit @johnpoz
            last edited by

            @johnpoz Where you out drinking with me last?

            Dude gave all his vlans DHCP addressess...... omg. Can't believe overlooked this possibility. Jumped to many conclusions after making all the wrong assumptions... Cheers John. Will get on my best phone call of the day now. 🤦

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            • johnpozJ Offline
              johnpoz LAYER 8 Global Moderator @tpit
              last edited by

              @tpit Glad I could help - customers do crazy shit sometimes.. I just have to shake my head at some of the setups I have seen ;)

              An intelligent man is sometimes forced to be drunk to spend time with his fools
              If you get confused: Listen to the Music Play
              Please don't Chat/PM me for help, unless mod related
              SG-4860 25.07 | Lab VMs 2.8, 25.07

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              • T Offline
                tpit @johnpoz
                last edited by

                @johnpoz This is our only customer with access to his access switches so he can do some simple tagging himself... :)

                Anyways, you made my incident ticket a work order ticket so I owe you one... 🍺

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                • johnpozJ Offline
                  johnpoz LAYER 8 Global Moderator @tpit
                  last edited by

                  @tpit said in VLAN 2 VLAN TCP traffic drops after 30 seconds:

                  customer with access

                  Well there you go - there is the RCA ;)

                  An intelligent man is sometimes forced to be drunk to spend time with his fools
                  If you get confused: Listen to the Music Play
                  Please don't Chat/PM me for help, unless mod related
                  SG-4860 25.07 | Lab VMs 2.8, 25.07

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                  • T Offline
                    tpit @johnpoz
                    last edited by

                    @johnpoz Ill be sure to tell him that... They usually require an RFO... ;)

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                    • johnpozJ Offline
                      johnpoz LAYER 8 Global Moderator @tpit
                      last edited by johnpoz

                      @tpit just hope he doesn't come back with getting you to up the timeout so he can run like that longer before the state gets closed ;) heheh

                      edit: Whats the old adage "customer is always right". I find this rarely the case when it comes to IT ;)

                      Giving customer access other than "read" is like handing a toddler a loaded handgun... They like to play with shiny stuff.. But once you load it - someone is going to get shot. And its going to be your fault ;)

                      An intelligent man is sometimes forced to be drunk to spend time with his fools
                      If you get confused: Listen to the Music Play
                      Please don't Chat/PM me for help, unless mod related
                      SG-4860 25.07 | Lab VMs 2.8, 25.07

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                      • T Offline
                        tpit @johnpoz
                        last edited by

                        @johnpoz Sticks and stones may break my bones but there will always be an end-user face-palming me to my doom... ;)

                        Still stupid I totally disregarded this possibility! :)

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