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    No DHCP on pfSense VLAN with Cisco Smart Switch

    Scheduled Pinned Locked Moved L2/Switching/VLANs
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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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        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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              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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                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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                                  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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                                      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
                                        SG-4860 24.11 | Lab VMs 2.8, 24.11

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

                                            @Cannondale one thing nice about the sg300 is shows pvid info ;)

                                            Both in the gui, and from cli

                                            That the gui lists P in the legend, but then doesn't show it, and the cli showing this confusing as hell

                                            Port : gi8
                                            Port Mode: 
                                            Gvrp Status: disabled
                                            Ingress Filtering: true
                                            Acceptable Frame Type: admitAll
                                            Ingress UnTagged VLAN ( NATIVE ): 1
                                             
                                            Port is member in: 
                                             
                                            Vlan               Name               Egress rule     Added by     
                                            ---- -------------------------------- ----------- ---------------- 
                                             10                 10                 Untagged          S         
                                            

                                            When I look at a interface with vlan on my sg300

                                            Port : gi1
                                            Port Mode: Access 
                                            Gvrp Status: disabled
                                            Ingress Filtering: true
                                            Acceptable Frame Type: admitAll
                                            Ingress UnTagged VLAN ( NATIVE ): 99
                                             
                                            Port is member in: 
                                             
                                            Vlan               Name               Egress rule     Added by     
                                            ---- -------------------------------- ----------- ---------------- 
                                             99                wan                 Untagged          S         
                                            
                                             
                                            Forbidden VLANS: 
                                            Vlan               Name               
                                            ---- -------------------------------- 
                                            
                                            

                                            That being said - I had no issues setting a interface to access in a vlan on the sg250, and it working as it should with the vlan tagged to pfsense via "trunk" port.. Even though the cli output is bonkers ;)

                                            There is clearly room for improvement in the info they show in the gui and the cli on the 250.. Why is showing the ingress untagged vlan as 1, when clearly that could not be the case if the interface is access in vlan 10..

                                            Notice on the 300, it shows the native same as the vlan used for egress as untagged.

                                            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
                                            SG-4860 24.11 | Lab VMs 2.8, 24.11

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