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    Getting a default denied rule after setting up the firewall rules

    Firewalling
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    • E
      Eugene
      last edited by

      # tcpdump -ni em0 host 91.199.45.221
      tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
      listening on em0, link-type EN10MB (Ethernet), capture size 96 bytes
      ...
      18:59:25.661775 IP 91.199.45.221.43367 > 10.0.0.10.23: S 3684512266:3684512266(0) win 5840 <mss 6="" 1899528742="" 1460,sackok,timestamp="" 0,nop,wscale="">18:59:25.662563 IP 10.0.0.10.49403 > 91.199.45.221.2121: . ack 341 win 253
      18:59:25.665811 IP 10.0.0.10.8 > 91.199.45.221.43367: S 4157337059:4157337059(0) ack 3684512267 win 4128 <mss 536="">18:59:27.667055 IP 10.0.0.10.1 > 91.199.45.221.43367: S 4157337059:4157337059(0) ack 3684512267 win 4128 <mss 536="">18:59:28.660593 IP 91.199.45.221.43367 > 10.0.0.10.23: S 3684512266:3684512266(0) win 5840 <mss 6="" 1899529492="" 1460,sackok,timestamp="" 0,nop,wscale="">18:59:28.662051 IP 10.0.0.10.8 > 91.199.45.221.43367: . ack 1 win 4128
      18:59:31.667660 IP 10.0.0.10.1 > 91.199.45.221.43367: S 4157337059:4157337059(0) ack 3684512267 win 4128</mss></mss></mss></mss> 
      

      I can't see your 10.0.0.10 responding with syn,ack. Can you? So, it does not accept tcp-connection at port 23.

      http://ru.doc.pfsense.org

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      • T
        TimDows
        last edited by

        Hmmm…

        Fact is that the 10.0.0.10 device is trying to reply to the telnet session because:

        • I can connect from inside the lan locally to this device;
        • The LAN firewall rules are picking up a reply generated by the telnet session trying to connect (See 2nd image in first post)
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        • E
          Eugene
          last edited by

          pfSense does not see syn,ack, it means your 10.0.0.10 does not route 91.199.45.221 back to pfSense.

          http://ru.doc.pfsense.org

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          • T
            TimDows
            last edited by

            @Eugene:

            pfSense does not see syn,ack, it means your 10.0.0.10 does not route 91.199.45.221 back to pfSense.

            Thanks for the help so far by the way!
            But 'unfortunately' the 10.0.0.10 can connect to this ip using http

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            • E
              Eugene
              last edited by

              I think it would be more clear if you could tcpdump on 10.0.0.10 to see whether it responds to  IP 91.199.45.221.43367 > 10.0.0.10.23: S
              Can you?

              http://ru.doc.pfsense.org

              1 Reply Last reply Reply Quote 0
              • T
                TimDows
                last edited by

                Sure I can check this:

                # tcpdump -ni em0 | grep 91.199.45.221
                tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
                listening on em0, link-type EN10MB (Ethernet), capture size 96 bytes
                22:12:57.604130 IP 91.199.45.221.34002 > 10.0.0.10.23: S 3047972562:3047972562(0) win 5840 <mss 6="" 1902431548="" 1460,sackok,timestamp="" 0,nop,wscale="">22:12:57.607788 IP 10.0.0.10.18 > 91.199.45.221.34002: S 564746040:564746040(0) ack 3047972563 win 4128 <mss 536="">22:12:59.608156 IP 10.0.0.10.1 > 91.199.45.221.34002: S 564746040:564746040(0) ack 3047972563 win 4128 <mss 536="">22:13:00.606330 IP 91.199.45.221.34002 > 10.0.0.10.23: S 3047972562:3047972562(0) win 5840 <mss 6="" 1902432298="" 1460,sackok,timestamp="" 0,nop,wscale="">22:13:00.607776 IP 10.0.0.10.18 > 91.199.45.221.34002: . ack 1 win 4128
                22:13:03.608388 IP 10.0.0.10.1 > 91.199.45.221.34002: S 564746040:564746040(0) ack 3047972563 win 4128 <mss 536="">22:13:06.606098 IP 91.199.45.221.34002 > 10.0.0.10.23: S 3047972562:3047972562(0) win 5840 <mss 6="" 1902433798="" 1460,sackok,timestamp="" 0,nop,wscale="">22:13:06.607501 IP 10.0.0.10.18 > 91.199.45.221.34002: . ack 1 win 4128
                22:13:11.608230 IP 10.0.0.10.1 > 91.199.45.221.34002: S 564746040:564746040(0) ack 3047972563 win 4128 <mss 536="">22:13:18.605858 IP 91.199.45.221.34002 > 10.0.0.10.23: S 3047972562:3047972562(0) win 5840 <mss 6="" 1902436798="" 1460,sackok,timestamp="" 0,nop,wscale="">22:13:18.607577 IP 10.0.0.10.18 > 91.199.45.221.34002: . ack 1 win 4128</mss></mss></mss></mss></mss></mss></mss></mss> 
                

                And the firewall messages:

                Might it have something to do that I'm using the loadbalacing service?

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                • E
                  Eugene
                  last edited by

                  If you think this```
                  22:12:57.604130 IP 91.199.45.221.34002 > 10.0.0.10.23: S 3047972562:3047972562(0) win 5840 <mss 6="" 1902431548="" 1460,sackok,timestamp="" 0,nop,wscale="">22:12:57.607788 IP 10.0.0.10.18 > 91.199.45.221.34002: S 564746040:564746040(0) ack 3047972563 win 4128</mss>

                  is correct then you are probably wrong.
                  Why you have in source 10.0.0.10.18 instead of 10.0.0.10.23 ??? I am confused…

                  http://ru.doc.pfsense.org

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                  • T
                    TimDows
                    last edited by

                    I haven't got the slithest idea what it could be.
                    I'm thinking of a reinstall with only 1WAN and then try to NAT something.

                    I'll let you know tomorrow (11 PM over here already)

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                    • E
                      Eugene
                      last edited by

                      I would blame 10.0.0.10 here.
                      Make local connection with network dumps.
                      … or good night -)

                      http://ru.doc.pfsense.org

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                      • T
                        TimDows
                        last edited by

                        Gonna try to connect a ubuntu machine here and try to open an external ssh session to it through pfSense.
                        Results are comming over :>)

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                        • T
                          TimDows
                          last edited by

                          well here some test results:

                          After connecting my 10.0.0.10 (Local device) to the modem directly all was working fine (Puts the problem definitely at the pfSense configuration)
                          I did a reinstall of my pfSense machine with the 1.2.3-RC1 image and created the LoadBalacer, placed the firewall rules so the Internet was working.
                          Unfortunately after creating the NAT and some more firewall rules, no connection could be made.

                          I now have a modem directly connected to my local device so incoming connections bypass the pfSense firewall. Not the best way but works for now. If I find a solution in the near future I'll be sure to post it here!

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                          • E
                            Eugene
                            last edited by

                            Can you make tcpdump on local device while connected directly to modem?

                            http://ru.doc.pfsense.org

                            1 Reply Last reply Reply Quote 0
                            • T
                              TimDows
                              last edited by

                              @Eugene:

                              Can you make tcpdump on local device while connected directly to modem?

                              That will be very hard (The local device is a Cisco router)
                              Guess I can connect my ubuntu machine directly and run a dump on there!

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                              • E
                                Eugene
                                last edited by

                                Fix it with ubuntu and then apply solution to cisco.

                                http://ru.doc.pfsense.org

                                1 Reply Last reply Reply Quote 0
                                • T
                                  TimDows
                                  last edited by

                                  @Eugene:

                                  Fix it with ubuntu and then apply solution to cisco.

                                  just tried to do this with ubuntu.
                                  I'm able to connect to ubuntu over the local network (telnet and ssh)
                                  Applying some NAT & Firewall rules give the same result as before, no syn,ack in tcpdump, while connecting from the interwebs.

                                  Getting very frustrated because its lovley weather over here ;>)

                                  Is there a 'workaround' for natting problems like this (Like turning off the firewall completely?)

                                  regards from the netherlands

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                                  • E
                                    Eugene
                                    last edited by

                                    It's lovely wheather here as well (sunny, 27C) but it should not affect our ability to fix this problem. Can you post tcpdumps of your local session to this ubuntu box and remote session (through pfsense)? Both dumps from ubuntu please.

                                    http://ru.doc.pfsense.org

                                    1 Reply Last reply Reply Quote 0
                                    • T
                                      TimDows
                                      last edited by

                                      FINALLY!!!

                                      I got it to work!

                                      The solution:

                                      • I used OPT1 or OPT3 for the incoming connections, change this to WAN
                                      • All devices connected where configured with static IP addresses, configure for DHCP and set up DHCP-server on LAN
                                      • Make some NAT and firewall rules to LAN & WAN
                                        +> Problem solved!

                                      Eugene thanks for the support so far!

                                      1 Reply Last reply Reply Quote 0
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