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    Subnets Routing Behind Layer 3 switch

    Scheduled Pinned Locked Moved Routing and Multi WAN
    19 Posts 3 Posters 3.4k Views
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    • A
      afrugone
      last edited by

      Thanks for answering my stupid questions, as you allready noticed I'm not a networking expert

      I mean there is a lot of equipment in the 172.27.108.0/22 network, that I can't control, and there are other subnets.

      :-\ And you are totally right I don't understand what is "transit network" :-\

      Please find attached my network configuration, The traffic you can see  from firewall rules must be from SQUID that is configured in pfesense, and perfectlly working

      Thanks

      ![net conf.jpg](/public/imported_attachments/1/net conf.jpg)
      ![net conf.jpg_thumb](/public/imported_attachments/1/net conf.jpg_thumb)
      ![net conf 1.jpg](/public/imported_attachments/1/net conf 1.jpg)
      ![net conf 1.jpg_thumb](/public/imported_attachments/1/net conf 1.jpg_thumb)

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      • johnpozJ
        johnpoz LAYER 8 Global Moderator
        last edited by

        Well how are you devices to access squid running on pfsense (which you didn't mention) before when your rule forces all traffic out your wan gateway.  That rule does not allow access to anything on pfsense like squid.. Just sends it out the wan gateway.

        So does stuff on your 10.164.56 network need to talk to stuff on your transit?  Which all have a gateway of pfsense 10.27.110.155??

        This causes asymmetrical routing

        asymet.png
        asymet.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
        Please don't Chat/PM me for help, unless mod related
        SG-4860 24.11 | Lab VMs 2.8, 24.11

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        • C
          coxhaus
          last edited by

          I am running a layer 3 switch behind pfsense.  There is a thread on this site under installation where I setup my configuration.  Looking at your config the only thing I see different is on the firewall rules under LAN is I have asterisk instead of default gateway name.  Probably won't make a difference.  I ran a /24 mask to start with in the transit network and it worked fine. I now use a 30 bit mask instead.  I am using a Cisco SG300-28 switch.

          I assume you are using an access port on the layer 3 switch and not a trunk port.

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          • A
            afrugone
            last edited by

            Thanks for your comments.

            I've just noticed a curious thing, the routing is working well to "outlook.office365.com", "www.cnn.com",  but not to "www.google.com", "www.ibm.com", I don't have any special rule for this. From Pfsense webconsole, al pings are 100% OK

            ping outlook.office365.com

            Haciendo ping a outlook.ms-acdc.office.com [40.102.35.114] con 32 bytes de datos:
            Respuesta desde 40.102.35.114: bytes=32 tiempo=236ms TTL=236
            Respuesta desde 40.102.35.114: bytes=32 tiempo=227ms TTL=236
            Respuesta desde 40.102.35.114: bytes=32 tiempo=227ms TTL=236
            Respuesta desde 40.102.35.114: bytes=32 tiempo=234ms TTL=236

            ping www.google.com

            Haciendo ping a www.google.com [172.217.28.228] con 32 bytes de datos:
            Tiempo de espera agotado para esta solicitud.
            Tiempo de espera agotado para esta solicitud.
            Tiempo de espera agotado para esta solicitud.
            Tiempo de espera agotado para esta solicitud.

            Estadísticas de ping para 172.217.28.228:
                Paquetes: enviados = 4, recibidos = 0, perdidos = 4
                (100% perdidos),

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            • A
              afrugone
              last edited by

              Hi,

              Thanks for your help, finally I found the problem, it was a bad defined rule in the switch router, at least I´ve learned a lesson about routing in PFsense.

              Thanks

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              • johnpozJ
                johnpoz LAYER 8 Global Moderator
                last edited by

                You still have a asymmetrical issue if devices on your transit need to be accessed from the downstream network(s) or the stuff on the transit access them.

                Simple to fix with just bringing up an actual transit between your L3 and pfsense vs using a host network as a transit network.

                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 24.11 | Lab VMs 2.8, 24.11

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                • C
                  coxhaus
                  last edited by

                  John they way I handled the asymmetrical issue is to let the layer 3 switch handle all the local routing.  In effect the layer 3 switch is the gateway for all local traffic and pfsense is the gateway for all internet traffic.  It worked fine this way.

                  I decided I wanted my router in a VLAN by it self so I did move to using a 30 mask for the router VLAN.  But the layer 3 switch is still the gateway for all local LAN traffic and pfsense is the gateway for all internet traffic.

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                  • johnpozJ
                    johnpoz LAYER 8 Global Moderator
                    last edited by

                    "I decided I wanted my router in a VLAN by it self so I did move to using a 30 mask for the router VLAN"

                    So you created a transit ;) between the layer 3 and pfsense..

                    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 24.11 | Lab VMs 2.8, 24.11

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                    • C
                      coxhaus
                      last edited by

                      Yes I did move over to a /30 mask but not right away.  I ran a /24 mask for a couple of months with no problems.  The reason I moved to a /30 mask was to eliminate all the chattiness from the work stations slowing down the router to where all traffic going to the router VLAN is destined for the internet.  When workstations start talking to each other behind the scenes this causes the router to wait because it is on the same network.  By isolating the router and allowing the layer 3 switch to switch local traffic I have effectively removed all local bottle necks for the router.

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                      • johnpozJ
                        johnpoz LAYER 8 Global Moderator
                        last edited by

                        "The reason I moved to a /30 mask was to eliminate all the chattiness from the work stations slowing down the router to where all traffic going to the router VLAN is destined for the internet."

                        Huh ???

                        At a complete loss to why would there be workstations on a transit?  And why would devices on a network talking to each other have anything to do with your router - are you using a HUB?

                        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 24.11 | Lab VMs 2.8, 24.11

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                        • C
                          coxhaus
                          last edited by

                          @johnpoz:

                          "The reason I moved to a /30 mask was to eliminate all the chattiness from the work stations slowing down the router to where all traffic going to the router VLAN is destined for the internet."

                          Huh ???

                          At a complete loss to why would there be workstations on a transit?  And why would devices on a network talking to each other have anything to do with your router - are you using a HUB?

                          What we are talking about John is all because you said asymmetrical routing does not work.  I said it does if you set it up right.  I used it for a while with workstations on the same network.  I later then changed for other reasons other then it did not work.

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                          • johnpozJ
                            johnpoz LAYER 8 Global Moderator
                            last edited by

                            "asymmetrical routing does not work.  I said it does if you set it up right."

                            Yeah you can make it work with host routing, or source natting.  Or allowing your firewall out of state traffic.. etc. etc..

                            Does not matter if you "can make it work".. The point it is setting it up in the first place is just plain BORKED!!  If you condone or promote anyone running a asymmetrical network.. You for sure should not be in the networking biz that is for damn freaking sure!  Sorry that is not ment as personal attack in anyway.. Its just stating my honest to goodness opinion.

                            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 24.11 | Lab VMs 2.8, 24.11

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                            • C
                              coxhaus
                              last edited by

                              Maybe with pfsense it is hard but it is easy to setup using a layer 3 switch.  All you have to do is point the local traffic to the layer 3 switch.  It knows where everything is and will route or switch to the device.  Nothing hard.  It is a good way to bring a layer 3 switch into the fold without disrupting normal operations.

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