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    Same Networks in different VLANs

    Scheduled Pinned Locked Moved L2/Switching/VLANs
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    • V
      viragomann @lucderheld
      last edited by

      @lucderheld
      Bridging interfaces is basically only recommended if there is no other option, i.e. if your really need both sides to be in the same L2 network. From your upper post, I was thinking you're looking for this.

      @lucderheld said in Same Networks in different VLANs:

      @viragomann
      Hmm, I want to keep the networks separated from each other. Is this possible too?

      Yes, you can still filter on member interfaces after they are added to a bridged.

      In System > Advanced > System Tunables there are two tunes which control the filtering typ:

      • net.link.bridge.pfil_member
      • link.bridge.pfil_bridge

      By default filtering on interface member is enabled.

      L 1 Reply Last reply Reply Quote 0
      • JKnottJ
        JKnott @lucderheld
        last edited by

        @lucderheld said in Same Networks in different VLANs:

        Oh that’s easy: the subnets have different vlan tags.

        Routers filter on address, not VLAN tag. A VLAN is no different than another interface in this respect. You're still back at the point of deciding which way to go when standing in front of the two apartment buildings.

        PfSense running on Qotom mini PC
        i5 CPU, 4 GB memory, 32 GB SSD & 4 Intel Gb Ethernet ports.
        UniFi AC-Lite access point

        I haven't lost my mind. It's around here...somewhere...

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        • JKnottJ
          JKnott @lucderheld
          last edited by

          @lucderheld

          You can have as many VLANs as you want. You can't have the same subnet on them, if you expect routing to work.

          PfSense running on Qotom mini PC
          i5 CPU, 4 GB memory, 32 GB SSD & 4 Intel Gb Ethernet ports.
          UniFi AC-Lite access point

          I haven't lost my mind. It's around here...somewhere...

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          • L
            lucderheld @JKnott
            last edited by

            @jknott said in Same Networks in different VLANs:

            @lucderheld said in Same Networks in different VLANs:

            Oh that’s easy: the subnets have different vlan tags.

            Routers filter on address, not VLAN tag. A VLAN is no different than another interface in this respect. You're still back at the point of deciding which way to go when standing in front of the two apartment buildings.

            Hmm. Two different Interfaces and two different vlans. This should be somehow doable.

            In your apartment example you would have two apartments with the same number in two different buildings.

            If this is not possible at the moment hopefully someone will build it. Like QinQ is doing it with vlans.

            JKnottJ 1 Reply Last reply Reply Quote 0
            • L
              lucderheld @viragomann
              last edited by

              @viragomann

              Sounds interesting! I will give it a try, but for now start with different subnets. Thanks for your input.

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              • JKnottJ
                JKnott @lucderheld
                last edited by

                @lucderheld said in Same Networks in different VLANs:

                Hmm. Two different Interfaces and two different vlans. This should be somehow doable.

                There is no way pfSense or any other router can have the same subnet on more than one interface/VLAN. It just won't work!

                PfSense running on Qotom mini PC
                i5 CPU, 4 GB memory, 32 GB SSD & 4 Intel Gb Ethernet ports.
                UniFi AC-Lite access point

                I haven't lost my mind. It's around here...somewhere...

                dotdashD 1 Reply Last reply Reply Quote 0
                • dotdashD
                  dotdash @JKnott
                  last edited by

                  @jknott
                  Not pfSense, correct, but any enterprise router has support for multiple routing tables. With Cisco, you can group interfaces by VRF- each VRF has a separate routing table. As I mentioned before FreeBSD supports this, and a feature request to put support in pfSense was submitted and ignored years ago. For more information, see the man page https://www.freebsd.org/cgi/man.cgi?query=setfib&apropos=0&sektion=0&manpath=FreeBSD+12.3-stable&arch=default&format=html

                  johnpozJ 1 Reply Last reply Reply Quote 0
                  • johnpozJ
                    johnpoz LAYER 8 Global Moderator @dotdash
                    last edited by johnpoz

                    @dotdash said in Same Networks in different VLANs:

                    but any enterprise router has support for multiple routing tables

                    Not sure I would say any ;) But sure most enterprise layer 3 switches or actual routers most likely do have support for VRF.. Those normally come with a pretty hefty price tag as well..

                    You could do it in TNSR I do believe

                    https://docs.netgate.com/tnsr/en/latest/routing/route-tables.html#virtual-routing-and-forwarding

                    Which is more their actual "enterprise" level product... While sure there are many enterprises using pfsense.. if your to the point where your needing to use VRFs.. Are you going to be running pfsense on some DIY box?

                    You could for sure have multiple networks with the same IP ranges in your network, you just can not currently route them on the same "router" VRF is a virtual router.. So its like running more than 1 router on the same hardware, etc.

                    You might be able accomplish what your after on the same hardware, by running different pfsenses as VMs on the hardware your wanting to use.

                    Where we use VRFs is for customer isolation, where we share hardware between customers in the DC, etc. Normally this hardware is pushing a lot of packets.. If was looking to replace one of those boxes it would most likely need to run TNSR just to be able to push the packets.

                    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

                    dotdashD 1 Reply Last reply Reply Quote 0
                    • dotdashD
                      dotdash @johnpoz
                      last edited by

                      @johnpoz
                      I don't have any need for multiple fibs in pfSense, and think the OP should just use different networks for the vlans. I was just replying the original statement that you can't have duplicate or overlapping networks on ANY router. I've dealt with VRFs mostly with Cisco gear, but I remember Extreme switches supported it and well as Juniper, etc. I'd make the argument that a router with multiple routing tables is just that and not actually several routers, so I stand by my original statement.

                      johnpozJ 1 Reply Last reply Reply Quote 0
                      • johnpozJ
                        johnpoz LAYER 8 Global Moderator @dotdash
                        last edited by

                        @dotdash said in Same Networks in different VLANs:

                        multiple routing tables is just that and not actually several routers

                        We could debate semantics I guess ;)

                        To "me" VRF is actual another router.. Since it is a whole set of new routing tables, and sure other interfaces.. Even if they are "virtual"

                        "Virtual routing and forwarding (VRF) is an IP-based computer network technology that enables the simultaneous co-existence of multiple virtual routers (VRs) as instances or virtual router instances (VRIs) within the same router."

                        think the OP should just use different networks for the vlans

                        We agree here ;)

                        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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