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    How to trunk 2 ports to switch on SG-2100?

    Scheduled Pinned Locked Moved L2/Switching/VLANs
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    • johnpozJ
      johnpoz LAYER 8 Global Moderator @worldHopp
      last edited by johnpoz

      If your going to run more than 1 vlan on the same port, ie your port 4 listed there.. Atleast 1 of them has to be tagged.. You can not run 2 untagged vlans on the same port and expect anything to work.. Then the port on your switch that is connected to this port has to be setup to match what you have tagged and what you have as native or untagged..

      You can tag all vlans if you want, etc.. But you show untagged there for both vlan 10 and 20 - this is never going to work correctly.

      You can only have 1 untagged vlan on a port at any given time.

      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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      • W
        worldHopp @johnpoz
        last edited by

        @johnpoz
        Oh right ok

        I just tried setting VLAN 20 as a tagged member so the members are 4t,5t
        VLAN 10 members = 4,5t

        I set ports 2-6 on the Aruba switch as tagged on VLAN 20 and Ports 7-8 as untagged on VLAN 10

        I also tried the reverse, setting VLAN 10 as tagged. Members= 4t, 5t and VLAN 20 as untagged. Members =4,5t
        I then set ports 2-6 on the Aruba switch as untagged on VLAN 20 and Ports 7-8 as tagged on VLAN 10

        So that the switch config matched the VLANs on the firewall. Neither configuration worked, devices were unable to get DHCP lease and only the native VLAN 1 untagged allocated 10.1.20.X

        Have I understood correctly?

        johnpozJ 1 Reply Last reply Reply Quote 0
        • johnpozJ
          johnpoz LAYER 8 Global Moderator @worldHopp
          last edited by johnpoz

          @worldhopp said in How to trunk 2 ports to switch on SG-2100?:

          I set ports 2-6 on the Aruba switch as tagged on VLAN 20

          Huh? Why would you do that? What do you have connected to them?

          Do they have more than 1 vlan on them? Are you setting the device connected to that port to use tags for some reason?

          The only port that needs to have vlans tagged is when there is more than 1 vlan on the port, say as uplink to another switch, or a AP or something. If you connecting a computer to said port then the vlan you want on that device would be untagged.

          Here is old drawing I did for some thread long time back - showing where tagged an untagged would be used

          example.png

          edit: Keep in mind that on your switch port your going to connect a device in a specific vlan, and its going to be untagged. You need to make sure the ports PVID is set to that vlan as well - so when the port sees ingress traffic that is no tagged it knows what vlan that traffic belongs too.

          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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          • W
            worldHopp @johnpoz
            last edited by worldHopp

            @johnpoz Thanks the image is making things more clear now.

            I think the problem is the initial trunk from the 2100, I have set my switch config up as per that image but still the untagged ports for the IoT VLAN 10 aren't getting DHCP lease. PVIDs are set correctly.

            The trunk port 1 has PVID of 1 - I take it that is correct?

            On the 2100 only for VLAN 10 Port 4 is tagged and Port 5 for uplink so it looks like 4t,5t
            VLAN 20 is untagged on port 4 so it looks like 4,5t

            I may just leave it as is but it means I'm not really taking advantage of the managed switch as this stage. As everything else has worked for my network upgrade apart from trunking these two VLANs to the switch.

            Anything else you could suggest? No problem if not

            thank you for the help

            johnpozJ 1 Reply Last reply Reply Quote 0
            • johnpozJ
              johnpoz LAYER 8 Global Moderator @worldHopp
              last edited by johnpoz

              @worldhopp said in How to trunk 2 ports to switch on SG-2100?:

              The trunk port 1 has PVID of 1 - I take it that is correct?

              Is your native vlan 1? The pvid of the port on the switch should be what vlan you want untagged traffic to be in..

              There is nothing saying you have to trunk anything... If you have ports available for uplink on your switch, and on your router there is no reason to carry vlans over the same physical port.

              Your still isolating the vlans on your switch, so yeah your taking advantage of its features. The only reason you need/want to run multiple vlans on the same physical is ports being available or not, etc.

              I personally run a few like that myself.. Since I have the ports to use.. I just trunk the vlans that don't do a lot of intervlan traffic and that use less bandwidth overall. My wireless vlans share an uplink..

              shared.png

              You can see that vlan 4 and 6 ride on the interface igb2, which also has an untagged vlan on it vlan 2, these 3 networks are mostly wireless devices on psk and guest. And they never talk to each other. But they do talk to my roku vlan, which is on its own interface.

              Even you used no tagged vlans at all - you would still be leveraging capabilities of your switch by actually isolating the different L2 - be it they are tagged or not to external devices.

              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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              • W
                worldHopp @johnpoz
                last edited by

                @johnpoz
                Thank you for your help. Everything is working now as planned. 👍

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

                  Glad you got it sorted.

                  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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                  • P
                    pdss @worldHopp
                    last edited by

                    @worldhopp What was the outcome here? I literally have the same issue. Would love know.

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                    • W
                      worldHopp @pdss
                      last edited by worldHopp

                      @pdss

                      At the time of this forum post I was still inexperienced when it comes to networking. I kind of had the wrong idea about ROAS.

                      Steps taken to enable router on a stick.

                      SG2100
                      Interfaces > Switch > VLANs
                      Enable 802.1q VLAN mode
                      Add the required VLANs to Netgate VLANs table - set required VLANs as tagged on the LAN port that connects to the switch and tagged on the uplink virtual port 5

                      Layer 2 Switch
                      Exact steps will vary depending on your model.... but generally...
                      Add VLANs to the VLAN table on your switch
                      Set the port that links back to Netgate as a trunk port or set all required VLANs as tagged on the port that links back to the Netgate
                      Then you can continue to setup your access aka untagged ports on the switch for end user devices

                      Your switch should now have a link back to the Netgate, enabling inter-VLAN routing.

                      Hope it helps

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                      • P
                        pdss @worldHopp
                        last edited by

                        @worldhopp I believe you just solved my issue! I was just visualizing tagged and untagged backward. I'll let you know for sure how it turns out.

                        Thanks for the response on this old forum.

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