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    Weird routing issue

    Scheduled Pinned Locked Moved Routing and Multi WAN
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    • johnpozJ Online
      johnpoz LAYER 8 Global Moderator
      last edited by

      "Using pfsense in 2 locations which are interconnected via dedicated network interface"

      This how you would normally do it..

      So in your site 1 you would have routes

      172.18.28.0/23    172.16.40.2
      192.168.1.0/24    172.16.40.2

      in site 2 you would have

      172.16.26.0/23 172.16.40.1

      Do have gateway to the other side of the transit in each site?

      What are your rules on your interfaces.  If your forcing traffic out a gateway say your internet gateway before you allow traffic using the normal pfsense routing then yeah your going to have problems.

      2sitesviatransit.png
      2sitesviatransit.png_thumb

      An intelligent man is sometimes forced to be drunk to spend time with his fools
      If you get confused: Listen to the Music Play
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      • R Offline
        rolandk
        last edited by

        yes, it`s like you visualized!

        we have a rule on the 172.16.26.0 lan which does policy based routing into WAN/Internet for ANY destination, but what i don´t understand is why for target 192.168.1.0/24 packets being correctly routed via the interconnect and for target 172.16.28.0/23 they are being routed via WAN/Internet - imho they should go the same way and that is what i don`t understand.

        if we add extra-rule for 172.18.28.0 to do policy based routing via Interconnect, it works - but why don`t we need that rule for 192.168.1.0, too ?

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        • johnpozJ Online
          johnpoz LAYER 8 Global Moderator
          last edited by

          dude if you want helping finding what is wrong in you rules - post them..

          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 25.07.1 | Lab VMs 2.8, 25.07.1

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          • R Offline
            rolandk
            last edited by

            here we go

            Rules for LAN interface on network 172.16.26.0/23

            SERVERLAN net (172.16.28.0/23)
            MGMTLAN net (172.16.37.0/24)
            VMLAN net (172.16.30.0/23)
            DMZ_TIER2 net (172.16.36.0/24)
            DMZ_UM_EXT net  (public ip subnet, ip/subnet not shown here because of data protection)

            IPv4+6 *  LAN net * This Firewall * * none   Pass any to this Firewall 
            IPv4 * LAN net * SERVERLAN net * * none   LAN to SERVERLAN 
            IPv4 * LAN net * MGMTLAN net * * none   LAN to MGMTLAN 
            IPv4 * LAN net * VMLAN net * * none   LAN to VMLAN 
            IPv4 * LAN net * 192.168.81.0/24 * * none   LAN to OpenVPN 
            IPv4 * LAN net * DMZ_UM_EXT net * * none   LAN to DMZ1
            IPv4 * LAN net * DMZ_TIER2 net * * none   LAN to DMZ2
            IPv4 * LAN net * * * WAN_UM none  everything else to internet

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            • johnpozJ Online
              johnpoz LAYER 8 Global Moderator
              last edited by

              is a screenshot really that hard??

              I don't see any rules that allow any traffic to the other sites 192.168.1/24 or 172.18.28/23

              is serverlan really 172.18.28??

              This is what you said this network was
              "172.18.28.0/23    172.16.40.1        UGS        igb2"

              From those rules I don't see how you could get across to anything..

              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 25.07.1 | Lab VMs 2.8, 25.07.1

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              • R Offline
                rolandk
                last edited by

                sorry, there is some infos in the description fields i do not want to have on the internet and im new to this forum so it didnt come to my mind.

                yes, from the ruleset i should not be able to connect to 192.168.0.x IP adresses, but i CAN.

                i can login via ssh to 192.168.1.50 for example and on the remote system, i see client`s ip 172.16.27.45 in netstat. so no nat or anything else in place.

                i don`t understand how this is possible as there is no rule which would allow or policyroute this.

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                • johnpozJ Online
                  johnpoz LAYER 8 Global Moderator
                  last edited by

                  Well if wan_um gateway can get there then you could get there.

                  Do you have any floating rules?

                  What other routes do you have?  When you do a traceroute to this 192.168.1.50 from your client 172.16.27.45 what do you show?

                  Have seen users have any any in their floating and then wonder why stuff is working even though they have a block on the interface ;)

                  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 25.07.1 | Lab VMs 2.8, 25.07.1

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                  • R Offline
                    rolandk
                    last edited by

                    no floating rules in place.

                    i investigated further and apparently the thing is all about "negate_networks"

                    https://forum.pfsense.org/index.php?topic=66776.45

                    i can see with "pfctl -T show -t negate_networks that it contains 192.168.1.0 (and others) but not 172.18.28.0. the question is , why.

                    will read into it further.

                    thanks for help so far

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                    • DerelictD Offline
                      Derelict LAYER 8 Netgate
                      last edited by

                      Because 192.168.1.0/24 is defined in a VPN somewhere, most likely.

                      You need to bypass policy routing for the 172.18.28.0/23 subnet.

                      Your problem is not routing in general, it is that you are policy routing out the WAN_UM gateway, which means everything not explicitly exempted in the rules above gets shoved that way without regard to the routing table. Why are you doing that? Is WAN_UM not the default gateway?

                      Chattanooga, Tennessee, USA
                      A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                      DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
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                      • R Offline
                        rolandk
                        last edited by

                        yes, 192.168.1.0 is also defined in a deactivated ipsec tunnel definition - apparently thats the reason why it exists in negate_networks, though - and thats the reason why 192.168.1.0 is (by chance) being routed the correct way and 172.18.28.0 not

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                        • johnpozJ Online
                          johnpoz LAYER 8 Global Moderator
                          last edited by

                          Dude as Derelict said and I stated in post 1 you need to allow rule above your rule that shoves everything down that gateway..
                          "If your forcing traffic out a gateway say your internet gateway before you allow traffic using the normal pfsense routing then yeah your going to have problems."

                          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 25.07.1 | Lab VMs 2.8, 25.07.1

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                          • R Offline
                            rolandk
                            last edited by

                            yes, i know.

                            but i was more curious why 192.168.1.0 was working THOUGH (i.e. without explicit allow rule).

                            you should know how your firewall works and how things behave.
                            you should be able to explain things and do not wonder about miraculous firewall behaviour.
                            that kann kill your security.

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                            • johnpozJ Online
                              johnpoz LAYER 8 Global Moderator
                              last edited by

                              Agreed, but since you have figured that out.. Now its time to correct your rules.

                              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 25.07.1 | Lab VMs 2.8, 25.07.1

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                              • R Offline
                                rolandk
                                last edited by

                                Your problem is not routing in general, it is that you are policy routing out the WAN_UM gateway, which
                                means everything not explicitly exempted in the rules above gets shoved that way without regard to
                                the routing table. Why are you doing that? Is WAN_UM not the default gateway?

                                WAN_UM is a gateway group, you cant set that as a default gateway and you can only route to a gw-group via policy routing, cant you ?

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                                • johnpozJ Online
                                  johnpoz LAYER 8 Global Moderator
                                  last edited by

                                  if you force a gateway, be it default or a group or whatever.. You have to allow rules above that if you want your clients to talk to other networks off pfsense that are not reachable through that gateway your forcing traffic through.  Is that simple!

                                  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 25.07.1 | Lab VMs 2.8, 25.07.1

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