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    Layer 2 Tunnel over Layer 3 (IPSec/GRE/GIF)

    Scheduled Pinned Locked Moved General pfSense Questions
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    • JKnottJ Offline
      JKnott
      last edited by

      The usual way to do that is to just route the VLANs through the VPN. No need to use layer 2 over the VPN. With OpenVPN, you'd use the TAP mode, for layer 2, but I'm not sure how well it handles VLANs.

      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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      • P Offline
        prx @JKnott
        last edited by

        @jknott

        At site B I have only the ISP Router (Cisco 1921), so I can't use OpenVPN. My goal is to use PfSense as a firewall for both the sites (A and B), how can I reach my goal?

        Thank you

        JKnottJ bingo600B 2 Replies Last reply Reply Quote 0
        • JKnottJ Offline
          JKnott @prx
          last edited by

          @prx

          Do you absolutely need L2? If all you want to do is have the same subnets available at each site, just route them as I said. Start with how you would do just one network and go from there.

          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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          • bingo600B Offline
            bingo600 @prx
            last edited by

            @prx said in Layer 2 Tunnel over Layer 3 (IPSec/GRE/GIF):

            how can I reach my goal?

            Get a second pfSense for SiteB.

            If you find my answer useful - Please give the post a šŸ‘ - "thumbs up"

            pfSense+ 23.05.1 (ZFS)

            QOTOM-Q355G4 Quad Lan.
            CPUĀ  : Core i5 5250U, Ram : 8GB Kingston DDR3LV 1600
            LANĀ  : 4 x Intel 211, DiskĀ  : 240G SAMSUNG MZ7L3240HCHQ SSD

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            • JKnottJ Offline
              JKnott @bingo600
              last edited by

              @bingo600 said in Layer 2 Tunnel over Layer 3 (IPSec/GRE/GIF):

              Get a second pfSense for SiteB.

              ????

              The normal way to connect two sites is to route through the VPN. It makes no difference how many subnets you do that with.

              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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              • stephenw10S Offline
                stephenw10 Netgate Administrator
                last edited by

                If you can't get another pfSense instance at Site B then what can the Cisco router do? That will determine what you use.

                What you really want there is a VXLAN but we're not there yet....

                Steve

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                • JKnottJ Offline
                  JKnott @stephenw10
                  last edited by

                  @stephenw10

                  I'm not familiar with that particular model but, generally, with Cisco you can do a lot. You could certainly route a couple of subnets over a VPN. Consider how you'd do this in pfsense. You'd set up the tunnel, which then provides an IP route between the two sites. Then you set up routing for each subnet you want to have at the other end. Cisco is all about routing, as that's where they started.

                  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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                  • bingo600B Offline
                    bingo600 @JKnott
                    last edited by bingo600

                    @jknott said in Layer 2 Tunnel over Layer 3 (IPSec/GRE/GIF):

                    @bingo600 said in Layer 2 Tunnel over Layer 3 (IPSec/GRE/GIF):

                    Get a second pfSense for SiteB.

                    ????

                    The normal way to connect two sites is to route through the VPN. It makes no difference how many subnets you do that with.

                    What does the above have to do with recommending the OP to use a pfSense on site B ?

                    Didn't the OP say L2 bridging ?
                    How would you do that on the Cisco ?

                    I'we done ipsec through GRE on Cisco's , prob. the closest you can come to "semi bridging" on a Cisco , and it was a PITA.

                    If L3 can be used , ipsec would be supported in both ends.

                    But IMHO , and considering the C1921 is "EOL/EOS" i still think that getting a 2'nd pfSense is the way to go.

                    /Bingo

                    If you find my answer useful - Please give the post a šŸ‘ - "thumbs up"

                    pfSense+ 23.05.1 (ZFS)

                    QOTOM-Q355G4 Quad Lan.
                    CPUĀ  : Core i5 5250U, Ram : 8GB Kingston DDR3LV 1600
                    LANĀ  : 4 x Intel 211, DiskĀ  : 240G SAMSUNG MZ7L3240HCHQ SSD

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                    • P Offline
                      prx
                      last edited by

                      Hi,

                      first of all thanks to all.
                      My goals, if it is possible, is bridge vlan 10 on site A with vlan 10 on site B and bridge and do the same thing for vlan 30. If it is not possible, the important thing is that, on site B, PCs connected on vlan 10 will receive via DHCP (DHCP Server configured on PfSense) an IP of the the subnet 192.168.10.0/24 and the same thing for clients connected on vlan 30. If this is not possible I can use for vlans 10 and 30 on site B different subnets, but in this case how can I achieve my goals? the navigation must be centralized on PfSense in Site A.

                      thank you

                      JKnottJ 1 Reply Last reply Reply Quote 0
                      • JKnottJ Offline
                        JKnott @bingo600
                        last edited by

                        @bingo600 said in Layer 2 Tunnel over Layer 3 (IPSec/GRE/GIF):

                        Didn't the OP say L2 bridging ?

                        One thing I've learned is it's often better to find out what the goal is, rather than what the person thinks has to be done. There's not a lot of reason to use L2 in a VPN. In this case, the OP has multiple VLANs/subnets he wants to pass through a VPN. What is the goal here? Putting VLANs through a VPN? Or connecting subnets at either end together. If the sole reason for L2 is to do that, then it's the wrong way to go.

                        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 Offline
                          JKnott @prx
                          last edited by

                          @prx

                          Do they have to be bridged, so that they have the same subnet addresses? If not, then just route.

                          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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                          • P Offline
                            prx @JKnott
                            last edited by

                            @jknott

                            Hi,
                            as I said, the subnet addresses can be different. All the traffic of all site B Vlans must be pass/fileter through the PfSense of Site A. Another important thing, as I said, PC on Vlan 10 (Site B) must receive via DHCP, the correct ip address (for example 192.168.50.0/24) and the same thing for clients on vlan 30 (for example 192.158.60.0/24).

                            Thank you

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                            • stephenw10S Offline
                              stephenw10 Netgate Administrator
                              last edited by

                              And to be clear you need to use the Cisco router at site B, you cannot replace it?

                              Because that would seem to rule out a L2 link anyway.

                              Can it do DHCP relay?

                              Steve

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                              • bingo600B Offline
                                bingo600 @stephenw10
                                last edited by

                                @stephenw10 said in Layer 2 Tunnel over Layer 3 (IPSec/GRE/GIF):

                                Can it do DHCP relay?

                                Cisco IoS , can do local DHCP server , or DHCP relay (ip helper)

                                If you find my answer useful - Please give the post a šŸ‘ - "thumbs up"

                                pfSense+ 23.05.1 (ZFS)

                                QOTOM-Q355G4 Quad Lan.
                                CPUĀ  : Core i5 5250U, Ram : 8GB Kingston DDR3LV 1600
                                LANĀ  : 4 x Intel 211, DiskĀ  : 240G SAMSUNG MZ7L3240HCHQ SSD

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                                • JKnottJ Offline
                                  JKnott @prx
                                  last edited by

                                  @prx

                                  Since the subnets don't have to be the same at each end, just route from each subnet/VLAN at one end to the corresponding subnet/VLAN at the other. There is no need to try to pass the VLAN tags between the sites. As for DHCP, you can either run DHCP servers at each site or use a relay agent to get DHCP from one site to the other.

                                  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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                                  • bingo600B Offline
                                    bingo600 @stephenw10
                                    last edited by

                                    @stephenw10
                                    Stephen
                                    Just for my info ...

                                    Not that i need it ... yet.

                                    Can we create a "Non interface" assigned DHCP scope on a pfSense. Aka get it to serve a scope that has no interface relation ? ... Ie. in relation with a remote site that can "DHCP forward"

                                    /Bingo

                                    If you find my answer useful - Please give the post a šŸ‘ - "thumbs up"

                                    pfSense+ 23.05.1 (ZFS)

                                    QOTOM-Q355G4 Quad Lan.
                                    CPUĀ  : Core i5 5250U, Ram : 8GB Kingston DDR3LV 1600
                                    LANĀ  : 4 x Intel 211, DiskĀ  : 240G SAMSUNG MZ7L3240HCHQ SSD

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                                    • JKnottJ Offline
                                      JKnott @bingo600
                                      last edited by

                                      @bingo600

                                      Wouldn't it be easier to just run a DHCP server at the other end? I could understand the need for relays back in the dark ages, when sites were connected with low bandwidth connections and you wanted to keep management local, but those days are long gone.

                                      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...

                                      DerelictD bingo600B 2 Replies Last reply Reply Quote 0
                                      • DerelictD Offline
                                        Derelict LAYER 8 Netgate @JKnott
                                        last edited by

                                        @jknott @bingo600 Or use a DHCP server other than the one in pfSense if it doesn't meet your needs.

                                        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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                                        • bingo600B Offline
                                          bingo600 @Derelict
                                          last edited by bingo600

                                          @derelict said in Layer 2 Tunnel over Layer 3 (IPSec/GRE/GIF):

                                          @jknott @bingo600 Or use a DHCP server other than the one in pfSense if it doesn't meet your needs.

                                          The question was just a "nice to know"

                                          I do not use pfsense dhcp at home.
                                          I use isc-dhcp & bind9 (Debian).

                                          Has a few advantages, at the cost of complexity & "vi" 😊
                                          But i love the dynamic registration , and the occational mac matching.

                                          I use pfSense dhcp at work, on all the sites.

                                          If you find my answer useful - Please give the post a šŸ‘ - "thumbs up"

                                          pfSense+ 23.05.1 (ZFS)

                                          QOTOM-Q355G4 Quad Lan.
                                          CPUĀ  : Core i5 5250U, Ram : 8GB Kingston DDR3LV 1600
                                          LANĀ  : 4 x Intel 211, DiskĀ  : 240G SAMSUNG MZ7L3240HCHQ SSD

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                                          • bingo600B Offline
                                            bingo600 @JKnott
                                            last edited by

                                            @jknott said in Layer 2 Tunnel over Layer 3 (IPSec/GRE/GIF):

                                            @bingo600

                                            I could understand the need for relays back in the dark ages,

                                            Actually my home pfsense relays requests to my linux dhcp.
                                            But hey are "same site".

                                            For doing remote relay, you have to take "line outage" , and thereby - Site outage (no dhcp) into account.

                                            I have had users complaining during a line outage, that they couldn't print their local word doc , to their local printer (dhcp outage) . They kind of accepted that they couldn't "see the server" , now that the line was down. But their PC & printer was in the same room .... That was hard to understand.

                                            All was because the IT Dept was "saving" , and wasn't interested in having a Win BDC at every site anymore.
                                            And no $$ for redundant lines.

                                            Well you get what you pay for, but local dhcp & dns can be essential.

                                            That's where pfSense is a super "One box fits it all"

                                            If you find my answer useful - Please give the post a šŸ‘ - "thumbs up"

                                            pfSense+ 23.05.1 (ZFS)

                                            QOTOM-Q355G4 Quad Lan.
                                            CPUĀ  : Core i5 5250U, Ram : 8GB Kingston DDR3LV 1600
                                            LANĀ  : 4 x Intel 211, DiskĀ  : 240G SAMSUNG MZ7L3240HCHQ SSD

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