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    DHCP over VLAN not working

    Scheduled Pinned Locked Moved DHCP and DNS
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    • DerelictD
      Derelict LAYER 8 Netgate
      last edited by

      That's all great but he said if he sets a static IP it works fine, so layer 2 might be intact.  Impossible to know what the deal is until he tells us exactly what he has done.

      No magic here.  Tagged, untagged, whatever. Set it up right for the particular circumstances and it works.

      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!
      Do Not Chat For Help! NO_WAN_EGRESS(TM)

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      • V
        VBS
        last edited by

        I know it's "Impossible to know what the deal is until he tells us exactly what he has done."

        I'd speculate that it'd be more likely for a switch or other device to not play nice with VLANs than for pfSense to mess things up.
        Of course, we won't know where to look until OP give us more info.

        I was just suggesting one thing to check before getting too technical - as fixing those settings on my switch solved my DHCP issues.

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        • E
          eddi1984
          last edited by

          Hi folks,

          sorry, should have provided some details.

          This is the setup:

          UNIFI AP –>(on port 25)--> Force10 S50 Switch -->(on port 48)--> pfsense (latest update)

          This is the setup on the UNIFI AP:
          Main SSID for employees with password, no VLAN assigned, net is 192.168.1.0/24  (EDIT: Typo corrected)
          Guest SSID for public with simple password, VLAN 5, net 10.0.0.0/28

          Force10 S50 Switch:
          *All ports are on VLAN 1 as default (not tagged). I think the switch only works with VLANs.
          Added VLAN5 for the port 25 where the UNIFI is connected to as a TAGGED port. So that port belongs to VLAN 1 & 5 (To allow net 192.168.1.0 & 10.0.0.0).

          PFSense:
          Default LAN setup, nothing fancy, Standard out of box setup. IP is 192.168.1.254 and with DHCP for the lan port. Port NIC is em1.
          Added VLAN5 on em1. Also added DHCP server for 10.0.0.0/28 for VLAN5. I also assigned a static IP to VLAN5 (10.0.0.1; DHCP range is 10.0.0.2-10.0.0.14)

          So, regular LAN is working just fine. The employee wifi is working just fine.

          When I try to connect to the guest wifi, it will not connect (on DHCP). If I assign the ip address manual (IP: 10.0.0.5; 255.255.255.240; Gateway 10.0.0.1; DNS 10.0.0.1), it starts working immediately. By working I mean, that browsing works and I cannot see the 192.168.1.0 network. I also have firewall rules that allow only certain ports and disallow to access to the 192.168.1.0 network. That seems to be working fine.

          So, I hope this helps, if you need something clarified, let me know.

          Cheers,

          Eddi

          PS: I saw the similar post, after posting my reply. Just to clarify, I am not the person posting here: https://forum.pfsense.org/index.php?topic=97816.0.

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          • DerelictD
            Derelict LAYER 8 Netgate
            last edited by

            Main SSID for employees with password, no VLAN assigned, net is 192.168.0.0/24

            Is that a typo?  You say 192.168.1.0/24 everywhere else.

            Are you sure you set the right netmask in the guest DHCP server?

            Does the guest wifi get any DHCP at all or nothing?

            The last time I helped someone with something like this it turned out to be some DHCP security settings in the switch.

            You might have to packet capture on the em1_vlan5 interface to see what's actually going on.

            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!
            Do Not Chat For Help! NO_WAN_EGRESS(TM)

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            • E
              eddi1984
              last edited by

              Hi,

              I corrected the typo.

              The netmask cannot be set in the guest DHCP server (for VLAN5), its there automatically, because I assigned a static IP to VLAN 5 (10.0.0.1/28).

              The netmask is correct, I double checked it again.

              One thing that I thought of when I was writing the detailed description is: I have not added the port 48, where the pfsense/LAN (em1) is connected, to VLAN5. So the port 25 is tagged VLAN5 but not port 48.

              I will have to test it later to night when I am on site. Will report back.

              Any other ideas?

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              • jahonixJ
                jahonix
                last edited by

                You do know that you should never combine tagged and untagged traffic on the same interface, don't you? Not unless absolutely necessary.
                And avoid using VLAN 1 for anything else than nothing. It is used internally in lots of gear and sometimes cannot be changed.

                Configure your LAN as VLAN4 and the other as VLAN5 (or what have you), stack them on one physical interface and connect it to your switch as trunk.
                Setup the switch accordingly and you're ready to go.

                corrected typo

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                • DerelictD
                  Derelict LAYER 8 Netgate
                  last edited by

                  How do you expect pfSense to get traffic on VLAN5 if the port isn't tagged with VLAN5?

                  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!
                  Do Not Chat For Help! NO_WAN_EGRESS(TM)

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                  • E
                    eddi1984
                    last edited by

                    Hi,

                    @Derelict:

                    How do you expect pfSense to get traffic on VLAN5 if the port isn't tagged with VLAN5?

                    I am new to VLANs. Added port 48 to VLAN5 and its working now like a charm.

                    @jahonix:

                    You do know that you should never combine tagged and untagged traffic on the same interface, don't you? Not unless absolutely necessary.
                    And avoid using VLAN 1 for anything else than nothing. It is used internally in lots of gear and sometimes cannot be changed.

                    Configure your LAN as VLAN4 and the other as VLAN5 (or what have you), stack them on one physical interface and connect it to your switch as trunk.
                    Setup the switch accordingly and you're ready to go.

                    corrected typo

                    Yes I am aware of that, and in the process of setting up the VLANs properly.

                    Thank folks for the good thoughts on this.

                    Cheers,

                    Eddi

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                    • DerelictD
                      Derelict LAYER 8 Netgate
                      last edited by

                      I am new to VLANs. Added port 48 to VLAN5 and its working now like a charm.

                      The fact that it worked "flawless" with a static IP makes me think something is still probably pretty hosed somewhere.

                      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!
                      Do Not Chat For Help! NO_WAN_EGRESS(TM)

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                      • V
                        VBS
                        last edited by

                        What OP Has Now (in theory):

                        • End-to-end communication possible for both networks.
                        • DHCP working and isolated appropriately.

                        What OP Had (in theory):

                        • Communication with other devices on the guest network would be possible.
                        • Communication with psfense (and therefore DHCP) should not be possible.

                        If two-way communication with pfsense was possible for devices on the guest network, that raises other concerns:
                        Was VLAN5's traffic able to return to pfsense untagged somehow…?

                        or

                        That would make two-way communication possible, but not DHCP, as the lease request and assignment would be on different "interfaces"
                        It would also mean that you don't have complete isolation: Traffic from the guest network would be able to bypass the firewall to enter the Main network (but not return that way)…

                        To illustrate jahonix's suggestion:

                        This should improve isolation and ease-of-management as all traffic would be assigned to a specific VLAN from end-to-end.
                        I believe the recommended best practice for pfSense is to remove the untagged interface entirely and use only VLANs. (with the exception of VLAN1 - which should not be used at all: since OP's Force10 S50 switch uses it internally for untagged traffic)

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                        • DerelictD
                          Derelict LAYER 8 Netgate
                          last edited by

                          Right.  I don't have any Ubiquiti gear right now but I have used it in the past.  It seems to really like being managed on the untagged VLAN, unfortunately.

                          You put a lot of time into those diagrams.  Thanks, and welcome to the forum.

                          It's better to untag VLAN 4 and tag VLAN 5 to the APs than use VLAN 1.  I got tired of telling people to forget VLAN 1 exists when you start tagging and trunking traffic.

                          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!
                          Do Not Chat For Help! NO_WAN_EGRESS(TM)

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                          • jahonixJ
                            jahonix
                            last edited by

                            @Derelict:

                            … Ubiquiti ... really like being managed on the untagged VLAN

                            This leads to using tagged and untagged traffic on the same IF as kind of default. Really? Or do they have multiple IFs on the unit to separate VLAN feeds?

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                            • DerelictD
                              Derelict LAYER 8 Netgate
                              last edited by

                              I have tried to get them to deal with a tagged management VLAN and they reverted back to untagged for some reason.  Might have just been that code level but it left a bad taste in my mouth.

                              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!
                              Do Not Chat For Help! NO_WAN_EGRESS(TM)

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