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

    Scheduled Pinned Locked Moved General pfSense Questions
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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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        • stephenw10S Offline
          stephenw10 Netgate Administrator
          last edited by

          Circling back I think the answer here is that if you have to use that Cisco router at site B you will need to just route the traffic and have different subnets at each end.

          If you can replace it with pfSense there are more options but we would still recommend routing it with different subnets at each end.

          Steve

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          • P Offline
            prx
            last edited by

            Hi,

            at site B I have to use Cisco router, and following you advice, we will try to configure a tunnel GRE or IPSec.
            I'll keep you posted

            Thank you very much to all

            bingo600B 1 Reply Last reply Reply Quote 0
            • bingo600B Offline
              bingo600 @prx
              last edited by

              @prx

              Remember gre alone is unencrypted , it's just tunneling

              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,

                I am doing some tests using 2 pfsense (remeber that in production on site B I must use a Cisco Router). I created 2 GRE Tunnels and I can ping GRE Interfaces (from pfsense at site A to pfsense at site B and viceversa).
                The GRE interfaces are /30 subnets:
                GRE Tunnel 1 (for vlan 10)

                • 192.168.33.1/30 (Site A)
                • 192.168.34.2/30 (Site B)

                GRE Tunnel 2 (for vlan 30)

                • 192.168.34.1/30 (Site A)
                • 192.168.34.2/30 (Site B)

                Now the question is: how can I "bind" GRE Tunnel 1 (Site B) to vlan 10 and GRE Tunnel 2 (Site B) to Vlan 30? I ask it because all the traffic on vlan 10 at Site B must be forward at vlan 10 at site A (DHCP and all kind of traffic), and the same thing for vlan 30.
                Another question: At Site A, in addition to the GRE interfaces, do I need to create any particular interfaces?

                Thank you

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                • P Offline
                  prx
                  last edited by prx

                  Ok,

                  in my tests now I have the following interfaces (in addition to the GRE):
                  Site A:

                  • Test 1 (Vlan 10): 192.168.55.1/24
                  • Test 2 (Vlan 30): 192.168.56.1/24

                  Site B:

                  • Test 1 (Vlan 10): 192.168.45.1/24
                  • Test 2 (Vlan 30): 192.168.46.1/24

                  Now the goal is to forward all the traffic of clients in Vlan A at Site B to the interface Test 1 (Vlan 10) at Site A, and, if it is possible, the clients at site B should receive their ip via a dhcp server enabled on the pfsense at site A.
                  The same thing for vlan 30...
                  Then for internet navigation of the clients at Site B is it enough to nat the subnets? Do I have to configure static routes?

                  Thank you

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                  • P Offline
                    prx
                    last edited by

                    Ok,

                    I went ahead with my tests and now i can surf the internet via the GRE Tunnel from the clients on vlan 10 at Site B. The only thing left to do is the implementation of the DHCP Server on PfSense at Site A, so the clients at Site B receive the right IPs:

                    • Vlan 10: 192.168.45.0/24
                    • Vlan 30: 192.168.46.0/24

                    How can I achieve this goal?

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

                      @prx

                      Are you sure you want to send company traffic over an unencrypted link?

                      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

                        Mmm, I always assume GRE over IPSec but....

                        You will need to setup a dhcp relay at site B pointing to a dhcp server at site A. However that probably can't be pfSense since there is no way to add a dhcp server for a subnet it does not have an interface in.

                        Steve

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                        • P Offline
                          prx @stephenw10
                          last edited by

                          @stephenw10

                          at this time I am doing only some tests. So, if I understood well, I can't use PfSense as DHCP Server at Site A...and if I will use IPSec VTI instead of GRE Tunnel?

                          Thank you

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                          • stephenw10S Offline
                            stephenw10 Netgate Administrator
                            last edited by

                            It wouldn't make any difference in terms of the dhcp server.

                            I would use routed IPSec there if the other router supports it if only because there are issues with GRE/IPSec in pfSense which it's better to avoid. And you definitely want to use encryption.

                            Steve

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