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    LAN Interface no carrier

    Scheduled Pinned Locked Moved General pfSense Questions
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    • B
      Bruzzler
      last edited by

      Hello,

      I have the following problem,

      I have a LAN interface on the pfsense.An access point is connected to the LAN interface. The problem is that I have activated dhcp and then the internet works via the access point, but a few seconds later the LAN says no carrier, i.e. no connection. I have tested the patch cables and NIC, everything works, only after activating DHCP for the LAN does this problem occur.

      thanks in advance.

      My Home Lab:

      WAN / Internet
      :
      : ISP
      :
      .--------.
      |FritzBox|
      '--------'
      |
      WAN | (currently no exposed host)
      |
      .-------.
      |pfSense| 192.168.0.5
      '-------'
      |
      |
      LAN | 192.168.10.5 /24
      |
      .-------------------.
      |TP_link Archer C50 |
      '-------------------'
      |
      |
      |

      End devices

      GertjanG 1 Reply Last reply Reply Quote 0
      • GertjanG
        Gertjan @Bruzzler
        last edited by

        @Bruzzler said in LAN Interface no carrier:

        LAN says no carrier, i.e. no connection.

        Even when there is no traffic (no Ethernet packets coming in) there is always a constant "bit-stream", pulsing with the known 100 Mbit (old) rate, 1Gbit (current) or even 2,5 Gbit (power user) or an extreme 10 Gbit (lucky you).

        Where / what showed the no carrier message ?

        The origin of the message comes from the line driver driver on the NIC : there are no 'pulses' detected.
        This could mean :
        Broken NIC (more or less close by the plug)
        Broken cable.
        Broken NIC on the others side - the 'send' part.

        Other possibilities : both sides can probably auto detect the speed. This auto detection can fail .....
        Or this one : if you set the speed manually on one side to 10 Mbit / half duplex and the other side to 10 Gbit full duplex, then you will see the 'no carrier' message.

        What is the type/brand of the NIC ?

        No "help me" PM's please. Use the forum, the community will thank you.
        Edit : and where are the logs ??

        B 1 Reply Last reply Reply Quote 0
        • B
          Bruzzler @Gertjan
          last edited by Bruzzler

          @Gertjan thanks for the quick reply.

          According to the MAC, the manufacturer of the NIC is Realtek. It is a USB Ethernet adapter that is connected to the pfsense device. I have tested the ethernet adapter and cable, they work on other devices.
          pfsense.PNG
          pfsense.PNG

          GertjanG 1 Reply Last reply Reply Quote 0
          • GertjanG
            Gertjan @Bruzzler
            last edited by Gertjan

            @Bruzzler said in LAN Interface no carrier:

            the NIC is Realtek

            Copy exact these 4 words into Google ( www.google.com ), hit Enter, and read the first page for links.
            If you get really uncomfortable, don't worry, that's normal.

            Not sure ?
            Use youtube, and do the same thing. Now things will go downhill fast.

            The story always ends well.
            It start with : get an 'Intel' NIC ..... ๐Ÿ˜Š


            What about swapping WAN and LAN ?
            In this case the 'Realtek' won't be talking to the "TP_link Archer C50" anymore, but the Fritsbox.

            No "help me" PM's please. Use the forum, the community will thank you.
            Edit : and where are the logs ??

            B 1 Reply Last reply Reply Quote 0
            • B
              Bruzzler @Gertjan
              last edited by

              @Gertjan Hey,

              I have changed the interfaces, now I can only access via ssh. It looks like I have to get another NIC like you said. Does the NIC have to be connected to the PCI or is it ok if I get an Intel NIC with usb connection?

              1 Reply Last reply Reply Quote 0
              • stephenw10S
                stephenw10 Netgate Administrator
                last edited by

                Realtek NICs are bad. USB NICs are bad. USB Realtek NICs.... ๐Ÿ˜‰

                But not always. What is logged in pfSense when it disconnects? What's logged in the access point? Is it connected directly?

                Steve

                B 1 Reply Last reply Reply Quote 0
                • B
                  Bruzzler @stephenw10
                  last edited by

                  @stephenw10 I have the pfsense in the Fujitsu Futro S720 ThinClient, which has a NIC. Would it make sense to install a second NIC via the PCIe slot on this device? Is this even worthwhile for this device?

                  1 Reply Last reply Reply Quote 0
                  • stephenw10S
                    stephenw10 Netgate Administrator
                    last edited by

                    What CPU does it have?

                    But, yes, add another NIC if you can.

                    B 1 Reply Last reply Reply Quote 0
                    • B
                      Bruzzler @stephenw10
                      last edited by

                      @stephenw10 Hey :)
                      AMD GX-217GA CPU 1.65GHz, 2GB RAM

                      B 1 Reply Last reply Reply Quote 0
                      • B
                        Bruzzler @Bruzzler
                        last edited by

                        @Gertjan @stephenw10
                        Is it worth it?

                        1 Reply Last reply Reply Quote 0
                        • stephenw10S
                          stephenw10 Netgate Administrator
                          last edited by

                          @Bruzzler said in LAN Interface no carrier:

                          GX-217GA

                          Mmm, well that's pretty old but probably fine for basic use as long as your available WAN bandwidth isn't above, say, 600Mbps.

                          B 1 Reply Last reply Reply Quote 0
                          • B
                            Bruzzler @stephenw10
                            last edited by

                            @stephenw10 @Gertjan
                            I have a 100 mbps . I got a cheap USB ethernet from Dell. The problem is that I can't install another NIC or the cost is not worth it for the device. I have tested with the new adapter, but have the same problem, then I set both WAN and LAN interface to half duplex. It worked for 20 minutes. But I noticed that after I used more data with the client, the LAN interface switched off again. The internal NIC is also a Realtek.

                            It works, but not for long. My impression is that there is a data collision. I even had the case that both interfaces switched off. I am at a loss at the moment. I will try only the two usb ethernet as NIC and see how it works.

                            1 Reply Last reply Reply Quote 0
                            • stephenw10S
                              stephenw10 Netgate Administrator
                              last edited by

                              Half-duplex is pretty much always wrong. If you need to set anything fixed it would be at 100M Full Duplex. But you shouldn't need to.

                              I would use VLANs with a VLAN capable switch rather than USB Ethernet given the choice.

                              Try switching the NIC assignments. I assume the USB NIC is LAN currently? Make sure it's still the USB NIC that fails when it's the WAN.

                              B 1 Reply Last reply Reply Quote 0
                              • B
                                Bruzzler @stephenw10
                                last edited by

                                @stephenw10 Until now, WAN has always been my internal NIC.

                                1 Reply Last reply Reply Quote 0
                                • stephenw10S
                                  stephenw10 Netgate Administrator
                                  last edited by

                                  Ok, so try swapping it to LAN and see if the problem follows the USB NIC.

                                  It may not. You might find it 'just works' as the WAN.

                                  1 Reply Last reply Reply Quote 0
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