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    Multi lan subnet on same physical interface

    2.1 Snapshot Feedback and Problems - RETIRED
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    • X
      xbipin
      last edited by

      recent snaps have static mapping which also can hand out dns server, gateway etc if u try to add static mapping under dhcp server

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      • P
        podilarius
        last edited by

        If it a small enough number, I would just put them on static IPs. Otherwise, I don't know if this is possible.

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        • X
          xbipin
          last edited by

          just 2 clients at max

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          • P
            podilarius
            last edited by

            For just 2, I would just set them up with static IPs pointing to 2.1/24. Are they Laptops or something that requires the IP to be more dynamic?

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            • X
              xbipin
              last edited by

              but dhcp wont allow giving those ip out of the 0.1/24 subnet nor can i assign static maps in dhcp for 2.1/24 subnet. yes one is a laptop and the other a PC

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              • P
                podilarius
                last edited by

                That is because pfSense goes by the DHCP standard very strictly. You are only allowed to use one subnet per interface and it will only let you use the one assigned to the interface.

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                • X
                  xbipin
                  last edited by

                  so i guess its more suited for SOHO type of networks without the extra flexibility

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                  • A
                    anthonysomerset
                    last edited by

                    No it can do enterprise and complex installs but you will find in those environments they have switches that do Vlans and use Vlans to seperate the network

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                    • P
                      podilarius
                      last edited by

                      @xbipin:

                      so i guess its more suited for SOHO type of networks without the extra flexibility

                      Usually SOHO is where you have those crazy requirements like this. In the enterprise, like anthonysomerset said, they would use VLANs. They could also just use another NIC.
                      pfSense is quite flexible. You can use it at home all the way to a datacenter to an enterprise office.

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                      • X
                        xbipin
                        last edited by

                        considering datacenter, pfsense still cant give out subnet mask as 255.255.255.255 which usually isps do

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                        • P
                          podilarius
                          last edited by

                          I have been in 5 different datacenter setups and none handed out /32 addresses. Now I do know a couple of ISPs on DSL that did that, but they were home setups.

                          Update:
                          Actually none used DHCP even. They expected you to hard set an IP.

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                          • C
                            cmb
                            last edited by

                            No worthwhile colocation datacenter uses DHCP, they assign a dedicated VLAN to each customer. No ISPs assign /32 masks with the exception of point to point types of connectivity (PPP, PPPoE, etc.) where that's just how things work.

                            Real, serious networks don't put multiple subnets on the same broadcast domain. It's nuts the OP starts out with "i dont have a VLAN tagging switch", then goes on to claim this is some kind of "datacenter config". No, a datacenter would be using VLANs and doing things right, what you're describing is an amateur hack attempt that no one should ever do.

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                            • X
                              xbipin
                              last edited by

                              1and1 gives out /32, multacom used to earlier i guess and there r many data centers that give out /32 ips using dhcp

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                              • X
                                xbipin
                                last edited by

                                the part about VLAN, the reason i said that is coz i wanted to know if pfsense is capable of doing such a thing without a VLAN switch coz i dont have that as of now but would have to get one if it wasnt able to do the thing i wanted

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                                • C
                                  cmb
                                  last edited by

                                  Some large super low rent hosting providers will hand out /32s but very few. In that case it's a matter of doing things to scale a network extremely cheaply, it's still questionable, but it's one method you may see if you have a $5/month web hosting account. Most of us aren't thinking a $5/month web hosting account when you say "datacenter", no reputable colocation facility hands out IPs via DHCP. That's a technique to provide cheap crappy web hosting at large scale.

                                  There are OSes including BSDs and others that will not function with a /32 IP because they will not ARP their gateway because ARPing something off a locally connected subnet is technically wrong.

                                  What you're trying to do is a bad idea and to some degree impossible (serving multiple scopes off the same interface without statically defining everything in all but one scope isn't doable with anything). Handing out /32 DHCP IPs also doesn't do anything to prevent hosts from talking to each other where the person controls the host.

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                                  • X
                                    xbipin
                                    last edited by

                                    ok got it.

                                    now can some1 tell me which is the cheapest VLAN switch i can find for home networks.
                                    i wonder y switch firmware cant be hacked to enable VLAN tagging, most small switches use a realtek or broadcom chip

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                                    • C
                                      cmb
                                      last edited by

                                      Netgear GS108T is my personal favorite for a cheap managed fanless gigabit switch.

                                      What features a switch supports depends on what its hardware supports, it's not like a typical firewall or router box where you can run basically everything on a CPU, the hardware itself has to support such things. In an unmanaged switch, that hardware support isn't there and you can't hack the hardware short of completely replacing it.

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                                      • X
                                        xbipin
                                        last edited by

                                        well true and not true, most SOHO switches use a realtek chip which by default doesnt support managing it but its fairly easy to supply a signal to one of its pin and make it manageable using an external ic and i have seen many guys do it after which it starts supporting VLAN. most modern chips r a stripped down cpu and to make better use of it, most is done at the software level but in this case the chip firmware, if the chip were a dumb hardware without software it would do very limited number of tasks but would perform it much quicker thats y the need for a software is there. hardwrae might not support new technology but it definitely can if its just a software feature

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                                        • ?
                                          A Former User
                                          last edited by

                                          there is 2 different versions of the Netgear GS108 switch. the Unmanaged one and the Managed version..
                                          i have Never liked the Managed version myself as there GUI is Horrible but for the price its a Good switch.
                                          (im spoiled by Enterprise grade gear for switches)

                                          we have Servers in DataCenters all over the globe and I have never encountered one that does DHCP
                                          for us NOR would I want one. and Yes all of ours are on there OWN Vlan provided to the TOR (Top
                                          Of Rack) switch of ours that Feeds the PFsense box and then 60U worth of Gear..

                                          also there would be no way to seperate the subnets on the same Nic without Vlans let alone getting
                                          it to work.

                                          2 minutes with wireshark and you could be around any block unless you Vlan off stuff…

                                          i have personally seen the damn 255.255.255.255 netmask done in the enterprise and spent damn
                                          near a month undoing all the static configs. it was causing more nightmares for the IT staff than anything
                                          else.

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                                          • X
                                            xbipin
                                            last edited by

                                            could u explain what specific issues can 255.255.255.255 netmask cause so i know if those issues r a great deal on a SOHO network?

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