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    IPSEC firewall rules udp/4500

    Scheduled Pinned Locked Moved IPsec
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    • M
      mind12
      last edited by

      Hello,

      Please enlighten me, struggling to understand why my IPSEC mobile client can connect even if the udp/4500 rule is disabled.

      So OUTSIDE is my WAN interface udp/500, udp/4500(disabled), ESP is allowed beside my OpenVPN ports and "Disable all auto-added VPN rules." IS checked.
      I have tested on my notebook with a mobile hotspot and in the meantime checked the packets with wireshark.
      UDP/4500 with ESP payload is flowing seemlessly.

      Why can I connect if the 4500 rule is disabled? Is this some kind of stateful behaviour?

      WAN rules:
      c581a3ba-1ee9-4734-8708-508529dfdea8-image.png

      Thank you.

      keyserK 1 Reply Last reply Reply Quote 0
      • keyserK
        keyser Rebel Alliance @mind12
        last edited by

        @mind12 The two most obvious options:

        1: After you disable the rule you need to reload states if you used to connection up until disabling the rule. Otherwise the state is still present and allowed in pfSense.

        2: Du you by any chance have a floating rule allowing the traffic?

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

        M 1 Reply Last reply Reply Quote 0
        • M
          mind12
          last edited by

          @keyser
          Thank you, your assumption was great.
          It was option 1 and the previous states that had allowed the connection the new connection.
          I guessed if I disconnect the VPN properly the firewall states also disapper "instantly" but it's not the case. Maybe I should have waited a little bit more before testing the connection again.

          Anyway it's such a relief that not my firewall rules were bad with a firewall hole somewhere.

          1 Reply Last reply Reply Quote 1
          • M
            metisit @keyser
            last edited by

            @keyser said in IPSEC firewall rules udp/4500:

            @mind12 The two most obvious options:

            1: After you disable the rule you need to reload states if you used to connection up until disabling the rule. Otherwise the state is still present and allowed in pfSense.

            I was wondering if you refered to "Diagnostics > States >Reset States " or something else, because "Resetting the state table is disruptive, but clients may immediately reconnect provided they are still passed by the current firewall rules."

            M 1 Reply Last reply Reply Quote 0
            • M
              mind12 @metisit
              last edited by

              @metisit Hi, almost, Diagnostics/States/states and I manually removed the respective connections using the bin button.

              1 Reply Last reply Reply Quote 0
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