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    No DHCP on pfSense VLAN with Cisco Smart Switch

    Scheduled Pinned Locked Moved L2/Switching/VLANs
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    • P
      pete35 @Cannondale
      last edited by

      @Cannondale
      i tought the same. Johnpoz is great.

      can you post the whole page of the vlan 10 interface configuration on the firewall ?

      <a href="https://carsonlam.ca">bintang88</a>
      <a href="https://carsonlam.ca">slot88</a>

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      • DerelictD
        Derelict LAYER 8 Netgate @pete35
        last edited by

        If you pcap on the parent interface you will see all the VLAN tags there along with all traffic on all VLANs. If you pcap on the VLAN interface you will not see the tags.

        I sometimes create unnumbered pfSense interfaces on the parent (IPv4 and IPv6 set to None) just so I can pcap there.

        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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        • C
          Cannondale @pete35
          last edited by

          @pete35 said in No DHCP on pfSense VLAN with Cisco Smart Switch:

          can you post the whole page of the vlan 10 interface configuration on the firewall ?

          vlan10 is configured for access mode on ge24
          vlan20 is configured for general mode on ge20

          Screenshot from 2023-05-24 08-33-22.png

          Screenshot from 2023-05-24 08-33-55.png

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          • P
            pete35 @Derelict
            last edited by

            @Derelict
            thank you. i already found it. Wireshark shows the vlan tag under each packet. yo need to open a packet to see the vlan 802.1q information.

            <a href="https://carsonlam.ca">bintang88</a>
            <a href="https://carsonlam.ca">slot88</a>

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            • P
              pete35 @Cannondale
              last edited by

              @Cannondale

              Maybe we can do another configuration:

              if you have a free port on your Pfsense, just configure it as LAN port with the IP address of your VLAN 10, first clear that VLAN 10 interface including that DHCP Server. Then configure two ports on the switch as access port in vlan 10. Connect one port directly to the second/new LAN port of pfsense, the other one to your workstation. You need to configure the DHCP Server at the new LAN port.

              Your workstation should be able to get an IP DHCP address from Pfsense in this VLAN 10.

              So no tagging is needed, if that is an issue with that switch.

              <a href="https://carsonlam.ca">bintang88</a>
              <a href="https://carsonlam.ca">slot88</a>

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              • C
                Cannondale @pete35
                last edited by

                @pete35
                wireshark doesn't seem to be noob friendly. I'm in a "packets must be specified" loop!

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                • C
                  Cannondale @pete35
                  last edited by

                  @pete35 said in No DHCP on pfSense VLAN with Cisco Smart Switch:

                  Maybe we can do another configuration

                  Working on it now

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                  • C
                    Cannondale @pete35
                    last edited by

                    @pete35 said in No DHCP on pfSense VLAN with Cisco Smart Switch:

                    Your workstation should be able to get an IP DHCP address from Pfsense in this VLAN 10

                    Got a vlan10 IP on the workstation. Didn't need to reconfigure the switch for vlan10 as port 23 and 24 were already configured for vlan10.

                    sw vlan.png

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                    • P
                      pete35 @Cannondale
                      last edited by

                      @Cannondale
                      That sounds good. Add more vlan 10 access ports to connect your servers and so on.
                      Until you find another solution with that tagging issue, this is as good as a trunked port and seperates the traffic.
                      Dont forget to add some firewall rules to limit the access to vlan 10 if you need this. Pfsense will route between Vlans.

                      <a href="https://carsonlam.ca">bintang88</a>
                      <a href="https://carsonlam.ca">slot88</a>

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                      • P
                        pete35 @Cannondale
                        last edited by

                        @Cannondale said in No DHCP on pfSense VLAN with Cisco Smart Switch:

                        wireshark doesn't seem to be noob friendly. I'm in a "packets must be specified" loop!

                        @Cannondale
                        this sounds interesting. if you startup wireshark on your interface of a workstation, it should work out of the box. So maybe there is something crazy on your network at all. Did you select the correct running interface?

                        if you generate a tcpdump file with "tcpdump -i interface -e -w dumpfile.pcap" you can open it with wireshark and you can save captured wireshark packets into a file for later analysis.

                        <a href="https://carsonlam.ca">bintang88</a>
                        <a href="https://carsonlam.ca">slot88</a>

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                        • C
                          Cannondale @pete35
                          last edited by

                          @pete35
                          Plugged the test Linux workstation into switch port 20 (vlan20).
                          I was able to create a dumpfile.pcap file on pfSense and open it on another machine in Wireshark. As a non-Network Engineer, what should I look for?

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                          • C
                            Cannondale @pete35
                            last edited by

                            @pete35 said in No DHCP on pfSense VLAN with Cisco Smart Switch:

                            if you startup wireshark on your interface of a workstation, it should work out of the box.

                            This is what I was seeing after entering some host information:

                            wireshark.png

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                            • P
                              pete35 @Cannondale
                              last edited by

                              @Cannondale

                              looks like it needs some more parameters on startup or needs some more priviledges (root?)
                              check the "-c" parameter and maybe check all this here:
                              https://adamtheautomator.com/wireshark-linux/

                              <a href="https://carsonlam.ca">bintang88</a>
                              <a href="https://carsonlam.ca">slot88</a>

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                              • P
                                pete35 @Cannondale
                                last edited by pete35

                                @Cannondale said in No DHCP on pfSense VLAN with Cisco Smart Switch:

                                Plugged the test Linux workstation into switch port 20 (vlan20).

                                Do you need another vlan ? Or is this just for investigation?
                                You can configure another vlan with the same trick, if you have more interfaces on the pfsense.

                                If you can, you may wipe out the whole configuration on the switch and reset it to an initial state. Configure it then only on the GUI. There are a lot of configuration options, maybe not shown on the cli. So if something is hidden, it may influence this crazy vlan issue.

                                https://www.cisco.com/c/dam/en/us/td/docs/switches/lan/csbss/sf_sg250/quick_start/guide/en_US/78-100762-01A0.pdf

                                <a href="https://carsonlam.ca">bintang88</a>
                                <a href="https://carsonlam.ca">slot88</a>

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                                • C
                                  Cannondale @pete35
                                  last edited by

                                  @pete35 said in No DHCP on pfSense VLAN with Cisco Smart Switch:

                                  Do you need another vlan ? Or is this just for investigation?

                                  Both. Ultimately need to confirm whether the switch is having an issue with tags. If not a config issue, I will replace it.

                                  @pete35 said in No DHCP on pfSense VLAN with Cisco Smart Switch:

                                  You can configure another vlan with the same trick, if you have more interfaces on the pfsense.

                                  Understood. I'm not a network expert but I recall that this is called segmentation. My quad port card in the pfSence server is full now. It appears that using additional NIC ports to segregate the LAN is a hardware approach as opposed to the vlan approach. My preference would be to use vlans unless a particular use case suggests that segmentation would work better.

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                                  • C
                                    Cannondale @pete35
                                    last edited by

                                    @pete35 said in No DHCP on pfSense VLAN with Cisco Smart Switch:

                                    looks like it needs some more parameters on startup or needs some more priviledges (root?)
                                    check the "-c" parameter and maybe check all this here:
                                    https://adamtheautomator.com/wireshark-linux/

                                    Thanks for the link! I'll check it out.

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                                    • J
                                      Jarhead @Cannondale
                                      last edited by

                                      @Cannondale I just skimmed this thread so I may have missed it but have you tried putting 2 ports in the same vlan and see if they can communicate?

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                                      • C
                                        Cannondale @Jarhead
                                        last edited by

                                        @Jarhead said in No DHCP on pfSense VLAN with Cisco Smart Switch:

                                        have you tried putting 2 ports in the same vlan and see if they can communicate?

                                        Thanks for chiming in Jarhead. Yes. Two untagged ports can communicate on a vlan. One connected to pfSense and the other connected to a Linux workstation.

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                                        • johnpozJ
                                          johnpoz LAYER 8 Global Moderator @Cannondale
                                          last edited by johnpoz

                                          @Cannondale Ok my sg250-08HP just got here.. clickly clicky running a vlan10..

                                          So either your switch is borked or you are doing something odd that we are missing... I didn't do anything to the switch other than boot it, give it an IP 192.168.200.9.. Plugged it into my igb4 interface that has 192.168.200.1/24

                                          Setup a vlan with 172.16.10.253/24 enabled dhcp..

                                          settingss.jpg

                                          switchf65809#term datadump                            
                                          switchf65809#sho run
                                          config-file-header
                                          switchf65809
                                          v2.5.8.15 / RCBS3.1_930_871_084
                                          CLI v1.0
                                          file SSD indicator encrypted
                                          @
                                          ssd-control-start
                                          ssd config
                                          ssd file passphrase control unrestricted
                                          no ssd file integrity control
                                          ssd-control-end cb0a3fdb1f3a1af4e4430033719968c0
                                          !
                                          !
                                          unit-type-control-start
                                          unit-type unit 1 network gi uplink none
                                          unit-type-control-end
                                          !
                                          vlan database
                                          vlan 10
                                          exit
                                          voice vlan state auto-triggered
                                          voice vlan oui-table add 0001e3 Siemens_AG_phone
                                          voice vlan oui-table add 00036b Cisco_phone
                                          voice vlan oui-table add 00096e Avaya
                                          voice vlan oui-table add 000fe2 H3C_Aolynk
                                          voice vlan oui-table add 0060b9 Philips_and_NEC_AG_phone
                                          voice vlan oui-table add 00d01e Pingtel_phone
                                          voice vlan oui-table add 00e075 Polycom/Veritel_phone
                                          voice vlan oui-table add 00e0bb 3Com_phone
                                          hostname switchf65809
                                          username user password encrypted $15$RNkCnVXJLcID4IKT$EDhJvPxPXJSsrsKvB8y0SMuwEaQn2SVckrVGzq6WfpOactj45CrUSHkc7nLpQAuAkdP72MS+2pTULQy7rIavcg== privilege 15
                                          ip ssh server
                                          sntp server 192.168.3.32 poll
                                          ip name-server  192.168.200.1
                                          !
                                          interface vlan 1
                                           ip address 192.168.200.9 255.255.255.0
                                           no ip address dhcp
                                          !
                                          interface GigabitEthernet1
                                           switchport mode trunk
                                           switchport trunk allowed vlan 1,10
                                          !
                                          interface GigabitEthernet8
                                           switchport access vlan 10
                                          !
                                          exit
                                          macro auto controlled
                                          ip default-gateway 192.168.200.1
                                          switchf65809#
                                          

                                          Now its currently running 2.5.8.15, plug into port 8 get an IP on the 172.16.10 network, plug into port 7 get an IP of vlan 1, 192.168.200..

                                          Going to update it to latest version - brb

                                          edit: ok back on 2.5.9.16, all working just fine..

                                          edit2: here is the dhcp from client I plugged into port 8 on the sg250, you can see it got an IP from my vlan 10 I setup on pfsense

                                          May 27 17:09:49 	dhcpd 	98873 	DHCPACK on 172.16.10.11 to d0:37:45:0e:8c:be via igb4.10
                                          May 27 17:09:49 	dhcpd 	98873 	DHCPREQUEST for 172.16.10.11 (172.16.10.253) from d0:37:45:0e:8c:be via igb4.10
                                          May 27 17:09:49 	dhcpd 	98873 	DHCPOFFER on 172.16.10.11 to d0:37:45:0e:8c:be via igb4.10
                                          May 27 17:09:48 	dhcpd 	98873 	DHCPDISCOVER from d0:37:45:0e:8c:be via igb4.10 
                                          

                                          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
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                                          • C
                                            Cannondale @johnpoz
                                            last edited by

                                            @johnpoz

                                            Sorry for the delay in responding. Just got back into town after traveling. Thanks for the additional information. Very helpful!
                                            I have an SG300 that arrived yesterday and still in a box. Will spark it up today to see what I find and report back.

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